Polarizing element, circularly polarizing plate, and image display device

ABSTRACT

An object of the present invention is to provide a polarizing element which has an excellent antireflection function as being applied to an image display device; and a circularly polarizing plate and an image display device, each of which has the polarizing element. The polarizing element of an embodiment of the present invention has an alignment film and an anisotropic light-absorbing film formed using a dichroic substance, in which a degree S of alignment of the anisotropic light-absorbing film is 0.92 or more, and an average refractive index n ave  at a wavelength of 400 to 700 nm of the alignment film is 1.55 to 2.0.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of PCT International Application No.PCT/JP2018/014815 filed on Apr. 6, 2018, which was published under PCTArticle 21(2) in Japanese, and which claims priority under 35 U.S.C. §119(a) to Japanese Patent Application No. 2017-077162 filed on Apr. 7,2017 and Japanese Patent Application No. 2017-119097 filed on Jun. 16,2017. The above applications are hereby expressly incorporated byreference, in their entirety, into the present application.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a polarizing element, a circularlypolarizing plate, and an image display device.

2. Description of the Related Art

In recent years, development of a flexible organic light emitting diode(OLED) has been in process and enhancement flexibility for each memberused has been in progress. Above all, a circularly polarizing plate usedfor preventing the reflection of external light is required to have ahigh degree of polarization and flexibility. In the related art, aniodine polarizer has been used in the circularly polarizing plate. Sincethe iodine polarizer is created by dissolving or adsorbing iodine in oronto a high-molecular material such as polyvinyl alcohol to stretch thefilm at a high ratio in one direction into a shape of a film, sufficientflexibility was not attained.

In this regard, use of a polarizing element in which a dichroicsubstance is applied onto a substrate such as glass and a transparentfilm and aligned using an intermolecular action or the like has beenstudied. For example, in JP54377448, a polarizing element which has ahigh concentration of a dichroic substance, is a thin film, and has ahigh degree of polarization has been proposed.

SUMMARY OF THE INVENTION

However, the present inventors have conducted studies, and as a result,they have found that in a case where the concentration of a dichroicsubstance is increased, the degree of alignment of the anisotropiclight-absorbing film can be increased, and therefore, although apolarizing element having a high degree of polarization is obtained, theantireflection function is lowered.

Therefore, an object of the present invention is to provide a polarizingelement which has an excellent antireflection function as being appliedto an image display device; and a circularly polarizing plate and animage display device, each of which has the polarizing element.

The present inventors have conducted extensive studies, and as a result,they have found that a polarizing element having an anisotropiclight-absorbing film having an alignment film and a dichroic substance,which has an excellent antireflection function in a case where a degreeS of alignment of the anisotropic light-absorbing film is 0.92 or moreand an average refractive index n_(ave) at a wavelength of 400 to 700 nmof the alignment film is 1.55 to 2.0, is obtained.

That is, the object can be accomplished by the following configuration.

[1] A polarizing element comprising:

an alignment film; and

an anisotropic light-absorbing film formed using a dichroic substance,

in which a degree S of alignment of the anisotropic light-absorbing filmis 0.92 or more, and

an average refractive index n_(ave) at a wavelength of 400 to 700 nm ofthe alignment film is 1.55 to 2.0.

[2] The polarizing element as described in [1],

in which an in-plane refractive index anisotropy Δn at a wavelength of550 nm of the alignment film is 0.10 or more.

[3] The polarizing element as described in [2],

in which the refractive index anisotropy Δn is 0.20 or more.

[4] The polarizing element as described in any one of [1] to [3],

in which the average refractive index n_(ave) is 1.55 to 1.80.

[5] The polarizing element as described in any one of [1] to [4],

in which an average refractive index n₅₅₀ at a wavelength of 550 nm ofthe alignment film is 1.55 to 1.75.

[6] The polarizing element as described in any one of [1] to [5],

in which a ratio of an average refractive index n₄₅₀ at a wavelength of450 nm of the alignment film to the average refractive index n₅₅₀ at awavelength of 550 nm of the alignment film is 1.0 or more.

[7] The polarizing element as described in any one of [1] to [6],

in which in a case where a refractive index of the anisotropiclight-absorbing film is defined as Nx₅₅₀ and a refractive index of thealignment film is defined as nx₅₅₀ in a direction in which an in-planerefractive index of the anisotropic light-absorbing film at a wavelengthof 550 nm is maximized, and

a refractive index of the anisotropic light-absorbing film is defined asNy₅₅₀ and a refractive index of the alignment film is defined as ny₅₅₀in a direction in-plane perpendicular to the direction in which thein-plane refractive index of the anisotropic light-absorbing film ismaximized,

Formula (1) is satisfied,|Nx ₅₅₀ −nx ₅₅₀ |+|Ny ₅₅₀ −ny ₅₅₀|<0.3  (Formula 1).

[8] The polarizing element as described in any one of [1] to [7],

in which a content of the dichroic substance is 8% to 22% by mass withrespect to a total solid content mass of the anisotropic light-absorbingfilm.

[9] The polarizing element as described in any one of [1] to [8],

in which a thickness of the alignment film is 10 nm to 100 nm.

[10] The polarizing element as described in any one of [1] to [9],

in which the alignment film is a photo-alignment film formed using aphotoactive compound having a photoreactive group having an azo group.

[11] The polarizing element as described in [10],

in which the photoactive compound is a compound represented by Formula(I) which will be described later,

in Formula (I) which will be described later, R²¹, R²², R²³, and R²⁴each independently represent a hydrogen atom or a substituent, providedthat at least one of R²¹, R²², R²³, or R²⁴ represents a carboxy group, asulfo group, or a salt thereof, and

in Formula (I) which will be described later, m represents an integer of1 to 4, n represents an integer of 1 to 4, o represents an integer of 1to 5, p represents an integer of 1 to 5, and in a case where m, n, o,and p are each an integer of 2 or more, a plurality of R²¹'s, R²²'s,R²³'s, and R²⁴'s may be the same as or different from each other,respectively.

[12] The polarizing element as described in [10] or [11],

in which the photo-alignment film includes a binder component having arefractive index of 1.50 to 1.60, and

a content of the binder component is 10% by mass or more with respect toa total solid content mass of the photo-alignment film.

[13] The polarizing element as described in any one of [1] to [9],

in which the alignment film is a film formed using either or both ofpolyamic acid and polyimide compounds.

[14] The polarizing element as described in any one of [1] to [13],

in which the dichroic substance includes a compound represented byFormula (II) which will be described later,

in Formula (II) which will be described later, R³¹, R³², R³³, R³⁴, andR³⁵ each independently represent a hydrogen atom or a substituent, R³⁶and R³⁷ each independently represent a hydrogen atom or an alkyl groupwhich may have a substituent, Q³¹ represents an aromatic hydrocarbongroup, an aromatic heterocyclic group, or a cyclohexane ring group,which may have a substituent, L³¹ represents a divalent linking group,A³¹ represents an oxygen atom or a sulfur atom, and R³⁶, R³⁷, and Q³¹may have a radically polymerizable group as a substituent.

[15] The polarizing element as described in any one of [1] to [14],

in which the anisotropic light-absorbing film exhibits reversewavelength dispersibility.

[16] The polarizing element as described in any one of [1] to [15],further comprising a substrate,

in which the polarizing element has the substrate, the alignment film,and the anisotropic light-absorbing film in this order.

[17] A circularly polarizing plate comprising:

the polarizing element as described in any one of [1] to [16]; and

a ¼ wavelength plate.

[18] An image display device comprising:

the polarizing element as described in any one of [1] to [16] or thecircularly polarizing plate as described in [17]; and

an image display element.

According to the present invention, it is possible to provide apolarizing element which has an excellent antireflection function asbeing applied to an image display device; and a circularly polarizingplate and an image display device, each of which has the polarizingelement.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, the present invention will be described in detail.

Description of configuration requirements described below may be made onthe basis of representative embodiments of the present invention in somecases, but the present invention is not limited to such embodiments.

Furthermore, in the present specification, a numerical range expressedusing “to” is used in a meaning of a range that includes the precedingand succeeding numerical values of “to” as the lower limit value and theupper limit value, respectively.

In addition, in the present specification, being parallel and beingperpendicular do not mean parallel and perpendicular in strict meanings,respectively, but mean ranges within ±5° from being parallel orperpendicular.

Moreover, in the present specification, (meth)acrylic acid is a genericterm indicating both of “acrylic acid” and “methacrylic acid”,(meth)acryloyl is a generic term indicating both of “acryloyl” and“methacryloyl”, (meth)acryloyloxy is a generic term indicating both of“acryloyloxy” and “methacryloyloxy”, and (meth)acrylate is a genericterm indicating both of “acrylate” and “methacrylate”.

In addition, in the present specification, a liquid crystallinecomposition and a liquid crystalline compound also encompass thosealready not exhibiting liquid crystallinity by curing or the like intheir concepts.

Degree of Alignment of Anisotropic Light-Absorbing Film

A degree S of alignment of the anisotropic light-absorbing film in thepresent invention is a value calculated according to the followingformula by setting the anisotropic light-absorbing film on a sampletable in a state where a linear polarizer is inserted into the side of alight source of an optical microscope (manufactured by NikonCorporation, product name “ECLIPSE E600 POL”), and measuring anabsorbance of the anisotropic light-absorbing film using a multi-channelspectrometer (manufactured by Ocean Optics Inc., product name“QE65000”).Degree of alignment: S=[(Az0/Ay0)−1]/[(Az0/Ay0)+2]

Az0: Absorbance with respect to polarized light in the direction of anabsorption axis of the anisotropic light-absorbing film

Ay0: Absorbance with respect to polarized light in the direction of atransmission axis of the anisotropic light-absorbing film

Refractive Index

A refractive index of each of the anisotropic light-absorbing film andthe alignment film in the present invention is a value measured using aspectral ellipsometer M-2000U manufactured by J. A. Woollam Co.

Specifically, at a predetermined wavelength t [nm], a direction in whichan in-plane refractive index of the anisotropic light-absorbing film ismaximized is defined as an x-axis, a direction perpendicular thereto isdefined as a y-axis, a direction normal to the in-plane is defined as az-axis, a refractive index in the x-axis direction is defined as Nxt, arefractive index in the y direction is defined as Nyt, and a refractiveindex in the z direction is defined as Nzt. For example, in a case wherethe measurement wavelength is 550 nm, a refractive index in the x-axisdirection is referred to as Nx₅₅₀, a refractive index in the y-axisdirection is referred to as Ny₅₅₀, and a refractive index in the z-axisdirection is referred to as Nz₅₅₀.

A refractive index of the alignment film in the embodiment of thepresent invention is also measured in the same manner as for therefractive index of the anisotropic light-absorbing film, and therefractive index in the x-axis direction (that is, a direction in whichthe in-plane refractive index of the anisotropic light-absorbing film ismaximized) is defined as nxt, the refractive index in the y-axisdirection is defined as nyt, and the refractive index in the z-axisdirection is defined as nzt. For example, in a case where themeasurement wavelength is 550 nm, the refractive index in the x-axisdirection is defined as nx₅₅₀, and in a case where the refractive indexin the y-axis direction is defined as ny₅₅₀, the refractive index in thez-axis direction is defined as nz₅₅₀.

The average refractive index n_(ave) at a wavelength range of 400 to 700nm of the alignment film in the embodiment of the present invention iscalculated by Formula (R1) using an average value nx_(ave) of therefractive index in the x-axis direction and an average value ny_(ave)of the refractive index in the y-axis direction by measuring nxt and nytat every nm in a wavelength range of 400 to 700 nm.Average refractive index n _(ave)=(nx _(ave) +ny _(ave))/2nx _(ave)=(nx ₄₀₀ +nx ₄₀₁ +nx ₄₀₂ + . . . +nx ₆₉₉ +nx ₇₀₀)/301ny _(ave)=(ny ₄₀₀ +ny ₄₀₁ +ny ₄₀₂ + . . . +ny ₆₉₉ +ny ₇₀₀)/301  (R1)

The average refractive index n₅₅₀ at a wavelength of 550 nm of thealignment film in the embodiment of the present invention is calculatedby Formula (R2).Average refractive index n ₅₅₀=(nx ₅₅₀ +ny ₅₅₀)/2  (R2)

The in-plane refractive index anisotropy Δn at a wavelength 550 nm ofthe alignment film in the embodiment of the present invention iscalculated by Formula (R3).Refractive Index Anisotropy Δn=nx ₅₅₀ −ny ₅₅₀  (R3)

Retardation

In the present invention, Re(λ) and Rth(λ) represent an in-planeretardation and a thickness direction retardation at a wavelength of λ,respectively. Unless otherwise specified, the wavelength of λ is definedas 550 nm.

In the present invention, Re(λ) and Rth(λ) are values measured at awavelength of λ in AxoScan OPMF-1 (manufactured by Opto Science, Inc.).By inputting the average refractive index ((Nx+Ny+Nz)/3) and the filmthickness (d (μm)) to AxoScan, it is possible to calculate:

Slow Axis Direction (°)Re(λ)=R0(λ)Rth(λ)=((Nx+Ny)/2−Nz)×d.

In addition, R0(λ) is expressed in a numerical value calculated withAxoScan OPMF-1, but means Re(λ).

The refractive indices Nx, Ny, and Nz used for the calculation of aretardation are measured using an Abbe refractometer (NAR-4T,manufactured by Atago Co., Ltd.) and a sodium lamp (λ=589 nm) as a lightsource. In addition, in a case where wavelength dependency is measured,the wavelength dependency can be measured with a multi-wavelength Abberefractometer DR-M2 (manufactured by Atago Co., Ltd.) in combinationwith an interference filter.

In addition, the values mentioned in Polymer Handbook (JOHN WILEY &SONS, INC.) and the catalogues of various optical films can be used. Thevalues of the average refractive indices of major optical films areexemplified below: cellulose acylate (1.48), cycloolefin polymer (1.52),polycarbonate (1.59), polymethyl methacrylate (1.49), and polystyrene(1.59).

Polarizing Element

The polarizing element of an embodiment of the present invention has analignment film and an anisotropic light-absorbing film including adichroic substance, in which a degree S of alignment of the anisotropiclight-absorbing film is 0.92 or more and an average refractive indexn_(ave) at a wavelength of 400 to 700 nm of the alignment film is 1.55to 2.0.

In a case where the polarizing element of the embodiment of the presentinvention is applied to an image display device, an excellentantireflection function can be exhibited. Details of reason thereof arenot clear, but is usually presumed as follows.

Examples of a method for improving the flexibility of an anisotropiclight-absorbing film including a dichroic substance include a method inwhich the thickness of an anisotropic light-absorbing film is decreased.In a case where such a thin film of the anisotropic light-absorbing filmis used, a method in which an anisotropic light-absorbing film having ahigh degree of alignment, obtained by increasing the degree of alignmentof a dichroic substance included in an anisotropic light-absorbing filmwhile increasing the concentration of the dichroic substance is used canbe mentioned as one of methods for obtaining a polarizing element havinga high degree of polarization.

However, in a case where an anisotropic light-absorbing film having ahigh degree of alignment (that is, a dichroic substance having a highdegree of alignment) is used, the refractive index anisotropy of thedichroic substance in the visible light region (at a wavelength ofapproximately 400 to 700 nm) is enhanced. As a result, it is thoughtthat the internal reflection at an interface between the anisotropiclight-absorbing film and an alignment film adjacent thereto isincreased, and thus, the antireflection function of the polarizingelement is lowered.

With regard to this problem, the present inventors have found that anexcellent antireflection function can be exhibited upon application ofan alignment film to an image display device in a case where arefractive index in the visible light region of the alignment film isset to be in a predetermined range. It is presumed that by setting therefractive index in the visible light region of the alignment film to bein a predetermined range as above, a refractive index in the visiblelight region of the anisotropic light-absorbing film and a refractiveindex in the visible light region of the alignment film are suitable,and the internal reflection at an interface between the anisotropiclight-absorbing film and the alignment film can be suppressed.

Alignment Film

The alignment film in the embodiment of the present invention has anaverage refractive index n_(ave) at a wavelength of 400 to 700 nm of1.55 to 2.0. With this, even in a case where an anisotropiclight-absorbing film having a high degree of alignment is used, apolarizing element having an excellent antireflection function isobtained.

The average refractive index n_(ave) of the alignment film is preferably1.55 to 1.80, and more preferably 1.60 to 1.80 from the viewpoint thatthe antireflection function of the polarizing element is more excellent.

The average refractive index n₅₅₀ at a wavelength of 550 nm of thealignment film is preferably 1.55 to 1.80, more preferably 1.55 to 1.75,and still more preferably 1.60 to 1.75. The light at a wavelength of 550nm is a light at a wavelength such that the light is easily visiblyrecognized to the human eyes. In a case where the average refractiveindex n₅₅₀ of the alignment film is within the range, the reflectedlight is hardly visibly recognized, and therefore, the antireflectionfunction of the polarizing element is more improved.

The in-plane refractive index anisotropy Δn at a wavelength of 550 nm ofthe alignment film is preferably 0.10 or more, and more preferably 0.20or more from the viewpoint that the antireflection function of thepolarizing element is further improved.

An upper limit value of the in-plane refractive index anisotropy Δn at awavelength of 550 nm of the alignment film is preferably 0.45 or less,more preferably 0.40 or less, and still more preferably 0.30 or lesssince the antireflection function of the polarizing element is lowered.

A ratio (n₄₅₀/n₅₅₀) of the average refractive index n₄₅₀ at a wavelengthof 450 nm of the alignment film to the average refractive index n₅₅₀ ata wavelength of 550 nm of the alignment film is preferably 1.0 or more,and more preferably 1.05 or more from the viewpoint that theantireflection function of the polarizing element is further improved.

An upper limit value of the ratio n₄₅₀/n₅₅₀) is preferably 1.2 or less,and more preferably 1.1 or less from the viewpoint that the reflectedlight of the polarizing element is suppressed from being tinted.

The thickness of the alignment film is preferably 10 to 10,000 nm, morepreferably 10 to 1000 nm, still more preferably 10 to 300 nm, andparticularly preferably 10 to 100 nm. In particular, in a case where thethickness of the alignment film is in a range of 10 to 100 nm, it ispossible to suppress the internal reflection by light on a shortwavelength side among the visible lights, using an interference action,and therefore, it is possible to suppress the reflected light from beingtinted. Thus, the antireflection function of the polarizing element isfurther improved.

In a case where an anisotropic light-absorbing film is coated and formedon an alignment film, it is preferable that the alignment film hassolvent resistance to an extent that the alignment film is not dissolvedby application of an anisotropic light-absorbing film composition. Inaddition, it is preferable that the alignment film has heat resistancein a heating treatment for removal of a solvent or for alignment ofliquid crystals.

The alignment film may be, but not limited to, a film formed using analignment polymer (for example, an alignment polymer compositionincluding an alignment polymer and a solvent which will be describedlater).

Examples of the alignment polymer include polyamides, gelatins,polyimides, polyamic acid, polyvinyl alcohols, alkyl-modified polyvinylalcohols, polyacrylamides, polyoxazoles, polyethyleneimine, polystyrene,polyvinylpyrrolidone, polyacrylic acids, and polyacrylic acid esters.These alignment polymers may be used alone or in combination of two ormore kinds thereof. Among these, either or both of the polyamic acid andthe polyimide compounds are preferably used from the viewpoints thatvarious refractive indices are easily set to be within theabove-mentioned range, that the solvent resistance is excellent and thatthe heat resistance is excellent.

The alignment film may be a photo-alignment film from the viewpointsthat various refractive indices are easily set to be within theabove-mentioned range, that the solvent resistance is excellent, andthat the heat resistance is excellent.

In the present invention, the photo-alignment film means a film formedusing a photoactive compound. The photo-alignment film is formed byapplying, for example, a composition (hereinafter also referred to as a“composition for forming a photo-alignment film”) including aphotoactive compound and a solvent onto, for example, a substrate whichwill be described later, and performing irradiation with polarized light(preferably polarized ultraviolet (UV)) to impart alignment regulatingforce.

The photoactive compound is a compound having a photoreactive group, andmay be either a polymer or a monomer. The photoreactive group refers toa group generating a liquid crystal alignment ability by irradiationwith light. Specifically, the photoreactive group causes alignmentinduction of molecules generated by irradiation with light, orphotoreaction that is an origin of a liquid crystal alignmentcapability, such as an isomerization reaction, a dimerization reaction,a photocrosslinking reaction, or a photodegradation reaction.

The photoreactive group preferably has an unsaturated bond, morepreferably has a double bond, and still more preferably has a grouphaving at least one bond selected from the group consisting of acarbon-carbon double bond (C═C bond), a carbon-nitrogen double bond (C═Nbond), a nitrogen-nitrogen double bond (N═N bond; also referred to as an“azo group”), and a carbon-oxygen double bond (C═O bond).

Examples of the photoreactive group having a C═C bond include a vinylgroup, a polyene group, a stilbene group, a stilbazole group, astilbazolim group, a chalcone group, and a cinnamoyl group.

Examples of the photoreactive group having a C═N bond include a grouphaving a structure of an aromatic Schiff's base, an aromatic hydrazone,or the like.

Examples of the photoreactive group having an N═N bond (azo group)include an azobenzene group, an azonaphthalene group, an aromaticheterocyclic azo group, a bisazo group, a formazan group, and a grouphaving azoxybenzene as a basic structure.

Examples of the photoreactive group having a C═O bond include abenzophenone group, a coumarine group, an anthraquinone group, and amaleimido group.

These photoreactive groups may have a substituent such as an alkylgroup, an alkoxy group, an aryl group, an allyloxy group, a cyano group,an alkoxycarbonyl group, a hydroxy group, a sulfonic acid group, and ahalogenated alkyl group.

Among these, the photoreactive group having an N═N bond (azo group) ispreferable, and the azobenzene group is more preferable, from theviewpoints that a polarization irradiation amount required forphoto-alignment is relatively small, that a photo-alignment film havingexcellent heat stability and temporal stability is easily obtained, andthat various refractive indices are easily set to be within theabove-mentioned range.

A photoactive compound having the photoreactive group having an N═N bond(azo group) is preferably a compound represented by Formula (I) from theviewpoints that a photo-alignment film having excellent heat stabilityand temporal stability is easily obtained and that various refractiveindices are easily set to be within the above-mentioned range.

In Formula (I), R²¹, R²², R²³, and R²⁴ (hereinafter also simply referredto as “R²¹ to R²⁴” in some cases) each independently represent ahydrogen atom or a substituent, provided that at least one of R²¹, . . ., or R²⁴ represents a carboxy group, a sulfo group, or a salt thereof.

In Formula (I), m represents an integer of 1 to 4, n represents aninteger of 1 to 4, o represents an integer of 1 to 5, p represents aninteger of 1 to 5, and in a case where m, n, o, and p are each aninteger of 2 or more, a plurality of R²¹'s to R²⁴'s may be the same asor different from each other, respectively.

Specific examples of the substituents represented by R²¹ to R²⁴ areshown below.

a carboxy group or a salt thereof (which may form a salt together withan alkali metal, and is preferably a carboxy group not forming a salt orforming a sodium salt, and more preferably the carboxy group forming asodium salt), a sun group or a salt thereof (which may form a salttogether with an alkali metal, and is preferably a sulfo group notforming a salt or forming a sodium salt, and more preferably the sulfogroup forming a sodium salt), an alkyl group (preferably an alkyl grouphaving 1 to 20 carbon atoms, more preferably an alkyl group having 1 to12 carbon atoms, and particularly preferably an alkyl group having 1 to8 carbon atoms; and examples of the alkyl group include a methyl group,an ethyl group, an isopropyl group, a tert-butyl group, an n-octylgroup, an n-decyl group, an n-hexadecyl group, a cyclopropyl group, acyclopentyl group, and a cyclohexyl group), an alkenyl group (preferablyan alkenyl group having 2 to 20 carbon atoms, more preferably an alkenylgroup having 2 to 12 carbon atoms, and particularly preferably analkenyl group having 2 to 8 carbon atoms; and examples of the alkenylgroup include a vinyl group, an allyl group, a 2-butenyl group, and a3-pentenyl group), an alkynyl group (preferably an alkynyl group having2 to 20 carbon atoms, more preferably an alkynyl group having 2 to 12carbon atoms, and particularly preferably an alkynyl group having 2 to 8carbon atoms; and examples of the alkynyl group include a propargylgroup and a 3-pentynyl group), an aryl group (preferably an aryl grouphaving 6 to 30 carbon atoms, more preferably an aryl group having 6 to20 carbon atoms, and particularly preferably an aryl group having 6 to12 carbon atoms; and examples of the group include a phenyl group, a2,6-diethylphenyl group, a 3,5-ditrifluoromethylphenyl group, a naphthylgroup, and a biphenyl group), a substituted or unsubstituted amino group(preferably an amino group having 0 to 20 carbon atoms, more preferablyan amino group having 0 to 10 carbon atoms, and particularly preferablyan amino group having 0 to 6 carbon atoms; and examples of the groupinclude an unsubstituted amino group, a methylamino group, adimethylamino group, a diethylamino group, and an anilino group),

an alkoxy group (preferably an alkoxy group having 1 to 20 carbon atoms,more preferably an alkoxy group having 1 to 10 carbon atoms, andparticularly preferably an alkoxy group having 1 to 6 carbon atoms; andexamples of the group include a methoxy group, an ethoxy group, and abutoxy group), an alkoxycarbonyl group (preferably an alkoxycarbonylgroup having 2 to 20 carbon atoms, more preferably an alkoxycarbonylgroup having 2 to 10 carbon atoms, and particularly preferably analkoxycarbonyl group having 2 to 6 carbon atoms; and examples of thealkoxycarbonyl group include a methoxycarbonyl group and anethoxycarbonyl group), an acyloxy group (preferably an acyloxy grouphaving 2 to 20 carbon atoms, more preferably an acyloxy group having 2to 10 carbon atoms, and particularly preferably an acyloxy group having2 to 6 carbon atoms; and examples of the an acyloxy group include anacetoxy group and a benzoyloxy group), an acylamino group (preferably anacylamino group having 2 to 20 carbon atoms, more preferably anacylamino group having 2 to 10 carbon atoms, and particularly preferablyan acylamino group having 2 to 6 carbon atoms; and examples of theacylamino group include an acetylamino group and a benzoylamino group),an alkoxycarbonylamino group (preferably an alkoxycarbonylamino grouphaving 2 to 20 carbon atoms, more preferably an alkoxycarbonylaminogroup having 2 to 10 carbon atoms, and particularly preferably analkoxycarbonylamino group having 2 to 6 carbon atoms; and examples ofthe alkoxycarbonylamino group include a methoxycarbonylamino group), anaryloxycarbonylamino group (preferably an aryloxycarbonylamino grouphaving 7 to 20 carbon atoms, more preferably an aryloxycarbonylaminogroup having 7 to 16 carbon atoms, and particularly preferably anaryloxycarbonylamino group having 7 to 12 carbon atoms; and examples ofthe aryloxycarbonylamino group include a phenyloxycarbonylamino group),a sulfonylamino group (preferably a sulfonylamino group having 1 to 20carbon atoms, more preferably a sulfonylamino group having 1 to 10carbon atoms, and particularly preferably a sulfonylamino group having 1to 6 carbon atoms; and examples of the sulfonylamino group include amethanesulfonylamino group and a benzenesulfonylamino group), asulfamoyl group (preferably a sulfamoyl group having 0 to 20 carbonatoms, more preferably a sulfamoyl group having 0 to 10 carbon atoms,and particularly preferably a sulfamoyl group having 0 to 6 carbonatoms; and examples of the sulfamoyl group include a sulfamoyl group, amethylsulfamoyl group, a dimethylsulfamoyl group, and a phenylsulfamoylgroup), a carbamoyl group (preferably a carbamoyl group having 1 to 20carbon atoms, more preferably a carbamoyl group having 1 to 10 carbonatoms, and particularly preferably a carbamoyl group having 1 to 6carbon atoms; and examples of the carbamoyl group include anunsubstituted carbamoyl group, a methylcarbamoyl group, adiethylcarbamoyl group, and a phenylcarbamoyl group),

an alkylthio group (preferably an alkylthio group having 1 to 20 carbonatoms, more preferably an alkylthio group having 1 to 10 carbon atoms,and particularly preferably an alkylthio group having 1 to 6 carbonatoms; and examples of the alkylthio group include a methylthio groupand an ethylthio group), an arylthio group (preferably an arylthio grouphaving 6 to 20 carbon atoms, more preferably an arylthio group 6 to 16carbon atoms, and particularly preferably an arylthio group having 6 to12 carbon atoms; and examples of the arylthio group include a phenylthiogroup), a sulfonyl group (preferably a sulfonyl group having 1 to 20carbon atoms, more preferably a sulfonyl group having 1 to 10 carbonatoms, and particularly preferably a sulfonyl group having 1 to 6 carbonatoms; and examples of the sulfonyl group include a mesyl group and atosyl group), a sulfinyl group (preferably a sulfinyl group having 1 to20 carbon atoms, more preferably a sulfinyl group having 1 to 10 carbonatoms, and particularly preferably a sulfinyl group having 1 to 6 carbonatoms; and examples of the sulfinyl group include a methanesulfinylgroup and a benzenesulfinyl group), a ureido group (preferably a ureidogroup having 1 to 20 carbon atoms, more preferably a ureido group having1 to 10 carbon atoms, and particularly preferably a ureido group having1 to 6 carbon atoms; and examples of the ureido group include anunsubstituted ureido group, a methylureido group, a phenylureido group),a phosphoric acid amido group (preferably a phosphoric acid amido grouphaving 1 to 20 carbon atoms, more preferably a phosphoric acid amidegroup having 1 to 10 carbon atoms, and particularly preferably aphosphoric acid amido group having 1 to 6 carbon atoms; and examples ofthe phosphoric acid amido group include a diethyl phosphoric acid amidogroup and a phenyl phosphoric acid amido group), a hydroxy group, amercapto group, a halogen atom (for example, a fluorine atom, a chlorineatom, a bromine atom, and an iodine atom), a cyano group, a nitro group,a hydroxamic acid group, a sulfino group, a hydrazino group, an iminogroup, a heterocyclic group (preferably a heterocyclic group having 1 to30 carbon atoms, and more preferably a heterocyclic group having 1 to 12carbon atoms, for example, a heterocyclic group having a heteroatom suchas a nitrogen atom, an oxygen atom, and a sulfur atom; and examples ofthe group include an imidazolyl group, a pyridyl group, a quinolylgroup, a furyl group, a piperidyl group, a morpholino group, abenzoxazolyl group, a benzimidazolyl group, and a benzthiazolyl group),and a silyl group (preferably a silyl group having 3 to 40 carbon atoms,more preferably a silyl group having 3 to 30 carbon atoms, andparticularly preferably a silyl group having 3 to 24 carbon atoms; andexamples of the silyl group include a trimethylsilyl group and atriphenylsilyl group).

These substituents may also be substituted with these substituents. Inaddition, in a case where two or more of the substituents are contained,the substituents may be the same as or different from each other.Further, if possible, the substituents may be bonded to each other toform a ring.

The substituent represented by each of R²¹ to R²⁴ may be a polymerizablegroup or may also be a group including a polymerizable group.

The group including a polymerizable group or a polymerizable group ispreferably a group which is present at a terminal of a molecule, thatis, at least one of R²³ or R²⁴ is preferably a group including apolymerizable group or a polymerizable group. In this case, at least oneof R²³ or R²⁴ is preferably substituted at the para-position withrespect to the azo group.

The polymerizable group is not particularly limited, but thepolymerization reaction is preferably an addition polymerization(including ring-opening polymerization) or a polycondensation reaction.In other words, the polymerizable group is preferably a polymerizablegroup capable of conducting the addition polymerization reaction or thepolycondensation reaction. Examples of the polymerizable group are shownbelow. In the following examples, Et represents an ethyl group and Prrepresents a propyl group.

As the polymerizable group, a polymerizable group conducting radicalpolymerization or cationic polymerization is preferable. As theradically polymerizable group, a generally known radically polymerizablegroup can be used, and very suitable examples of the radicallypolymerizable group include a (meth)acrylate group. As the cationicallypolymerizable group, a generally known cationically polymerizable groupcan be used, and specific examples of the cationically polymerizablegroup include an alicyclic ether group, a cyclic acetal group, a cycliclactone group, a cyclic thioether group, a spiro-ortho ester group, anda vinyloxy group. Among these, the alicyclic ether group and thevinyloxy group are very suitable, and the epoxy group, the oxetanylgroup, and the vinyloxy group are particularly preferable.

In Formula (I), R²¹ to R²⁴ are each preferably a hydrogen atom, acarboxy group, a sulfo group, a halogen atom, an alkyl group (preferablya halogenated alkyl group), an alkoxy group (preferably a halogenatedalkoxy group), a cyano group, a nitro group, an alkoxycarbonyl group, ora carbamoyl group, more preferably a hydrogen atom, a carboxy group, asulfo group, a halogen atom, a halogenated methyl group, a halogenatedmethoxy group, a cyano group, a nitro group, or a methoxycarbonyl group,and still more preferably a hydrogen atom, a carboxy group, a sulfogroup, a halogen atom, a cyano group, or a nitro group.

At least one of R²¹, . . . , R²⁴ is a carboxy group or a sulfo group.The substitution position of the carboxy group or the sulfo group is notparticularly limited, but from the viewpoint of a photoactive action, itis preferable that at least one R²¹ and/or at least one R²² is a sulfogroup, and it is more preferable that at least one R²¹ and at least oneR²² are each a sulfo group. Further, from the same viewpoint, it ispreferable that at least one R²³ and/or at least one R²⁴ are each acarboxy group, and it is more preferable that at least one R²³ and atleast one R²⁴ are each a carboxy group. It is also preferable that thecarboxy group is R²³ or R²⁴ substituted at the meta-position withrespect to the azo group.

In Formula (I), m represents an integer of 1 to 4, n represents aninteger of 1 to 4, o represents an integer of 1 to 5, and p representsan integer of 1 to 5. Preferably, m is an integer of 1 or 2, n is aninteger of 1 or 2, o represents an integer of 1 or 2, and p representsan integer of 1 or 2.

Specific examples of the compound represented by Formula (I) are shownbelow, but are not limited to the following specific examples.

No. R¹ R² R³ R⁴ E-1 —SO₃Na —H —COOH —OH E-2 —H —SO₃Na —COOH —OH E-3—SO₃Na —H —COONa —OH E-4 —H —SO₃Na —COONa —OH E-5 —CH₃ —H —COONa —OH E-6—H —CH₃ —COONa —OH E-7 —H —OCH₃ —COONa —OH E-8 —H —OCF₃ —COONa —OH E-9—H —Cl —COONa —OH E-10 —H —CN —COONa —OH E-11 —H —NO₂ —COONa —OH E-12—COOCH₃ —H —COONa —OH E-13 —CONH₂ —H —COONa —OH E-14 —SO₂NH₂ —H —COONa—OH E-15 —SO₃Na —H —COONa —OH E-16 —SO₃Na —H —CH₂OH —OH E-17 —H —SO₂Na—CH₂OH —OH E-18 —SO₃Na —H —COOH

E-19 —H —SO₃Na —COOH

E-20 —CH₃ —H —COONa

E-21 —H —CH₃ —COONa

E-22 —SO₃Na —H —CF₃

E-23 —H —SO₃Na —CF₃

E-24 —SO₃Na —H —COOH

E-25 —CH₃ —H —COONa

E-26 —SO₃Na —H —CF₃

The composition for forming a photo-alignment film may include one ormore kinds of additives in addition to the photoactive compound. Theadditive is added for the purpose of, for example, adjustment of therefractive index of the composition for forming a photo-alignment film.

The additive is preferably a binder component, and from the viewpoint ofcompatibility with the photoactive compound, a compound having ahydrophilic group and a (meth)acryloyloxy group is preferable. Examplesof the hydrophilic group include a hydroxy group, a carboxy group, asulfo group, and an amino group.

The additive may be added to an extent such that the alignmentcapability is not remarkably lowered.

In a case where an additive is used for the purpose of adjustment of therefractive index of the composition for forming a photo-alignment film,the refractive index (refractive index at a wavelength of 550 nm) of theadditive is preferably 1.40 to 1.60.

In particular from the viewpoint that in a case where the additive is abinder component, it becomes easier to adjust the refractive index ofthe photo-alignment film, the refractive index (refractive index at awavelength of 550 nm) of the binder component is preferably 1.40 to1.60, and more preferably 1.50 to 1.60.

From the viewpoint that the compound having a hydroxy group and a(meth)acryloyloxy group among the compounds having a hydrophilic groupand a (meth)acryloyloxy group has more excellent hydrophilicity, it ispreferable that the compound has two or more hydroxy groups. Specificexamples of such a compound include monoglycidyl ethers such as glycidyl(meth)acrylate; diglycidyl ethers of dihydric alcohols, such aspropylene glycol, butanediol, pentanediol, hexanediol, diethyleneglycol, dipropylene glycol, triethylene glycol, tripropylene glycol,tetraethylene glycol, polyethylene glycol, polypropylene glycol,neopentyl glycol, hydroxyl pivalic acid neopentyl glycol, bisphenol A,and ethoxylated bisphenol A; triglycidyl ethers of trihydric alcohols,such as trimethylolpropane, ethoxylated trimethylolpropane, propoxylatedtrimethylolpropane, and glycerin; an epoxy (meth)acrylate compoundobtained by reacting a glycidyl group of a glycidyl ether compound suchas polyglycidyl ethers or the like of polyhydric phenols having at leastone aromatic ring or alicycle (it should be noted that examples of thepolyhydric phenols as mentioned herein include bisphenol compounds oralkylene oxide adducts of the bisphenol compounds, such as bisphenol A,bisphenol F, and bisphenol S, phenol novolak, cresol novolak, oralkylene oxide adducts thereof), with a (meth)acrylic acid; and analcoholic (meth)acrylate compound obtained by reacting a (meth)acrylicacid with a portion of the hydroxy group of a polyol, such aspentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate,dipentaerythritol di(meth)acrylate, dipentaerythritol tri(meth)acrylate,dipentaerythritol penta(meth)acrylate, glycerin di(meth)acrylate,trimethylolpropane di(meth)acrylate, ditrimethylolpropanedi(meth)acrylate, ditrimethylolpropane tri(meth)acrylate,ditrimethylolpropane tetra(meth)acrylate, ditrimethylolpropanehexa(meth)acrylate, ethoxylated trimethylolpropane di(meth)acrylate,propoxylated trimethylolpropane di(meth)acrylate, andtris-2-hydroxyethyl isocyanurate di(meth)acrylate.

Examples of a commercially available product of the compound having ahydroxy group and a (meth)acryloyloxy group include DENACOL ACRYLATEDA-212, DA-111, DA-911 M, and DA-931 (product names, all manufactured byNagase Chemtex Corp.).

The number of the carboxy groups per molecule of the compound having acarboxy group and a (meth)acryloyloxy group among the compounds having ahydrophilic group and a (meth)acryloyloxy group is not particularlylimited from the viewpoint that the hydrophilicity of the carboxy groupis sufficiently high, and the number of the carboxy groups may be one ortwo or more.

However from the viewpoints that a solubility in an organic solvent isimproved and an improvement in the crystallinity of the compound can besuppressed, a smaller number the carboxy groups is more preferablewithin a range such that adhesiveness for adjacent layers and solventresistance can be maintained. In particular, in a case of a compoundhaving a carboxy group directly linked to an aromatic ring, the numberof the carboxy groups per molecule is preferably 2 or less.

Specific examples of the compound having a carboxy group and a(meth)acryloyloxy group include a compound having a carboxy group and atleast one or more (meth)acryloyloxy groups per molecule, such as2-(meth)acryloyloxyethyl hexahydrophthalate, 2-acryloyloxyethylphthalate, 2-methacryloyloxyethyl phthalate, and ethylene oxide-modifiedsuccinic acid acrylate, a compound obtained by adding an acid anhydridesuch as phthalic anhydride to a compound having a hydroxy group and a(meth)acryloyloxy group, such as 2-hydroxylethyl (meth)acrylate, and abenzoic acid derivative having an alkyl(oxy) group in which a(meth)acryloyloxy group is introduced to the terminal, as a substituent.

In a case of the benzoic acid derivative, the number of the alkyl(oxy)groups in which a (meth)acryloyloxy group is introduced to a terminal,as a substituent, may be 1 or more, but is preferably 1 to 3 from theviewpoint of ease of synthesis. Further, in a case of introduction of analkyl(oxy) group having a (meth)acryloyloxy group introduced at aplurality of terminals thereof, it is preferable to select a position tolower the symmetry of a molecule as the substitution position from theviewpoint of not extremely increasing the crystallinity.

Specific examples of the benzoic acid derivative include2-(ω-(meth)acryloyloxyalkyl(oxy))benzoic acid,2,3-di(ω-(meth)acryloyloxyalkyl(oxy))benzoic acid,2,4-di(ω)-(meth)acryloyloxyalkyl(oxy))benzoic acid,2,5-di(ω-(meth)acryloyloxyalkyl(oxy))benzoic acid,3-(ω-(meth)acryloyloxyalkyl(oxy))benzoic acid,3,4-di(ω-(meth)acryloyloxyalkyl(oxy))benzoic acid, and4-(ω)-(meth)acryloyloxyalkyl(oxy))benzoic acid, in which the number ofthe methylene groups in the alkyl chain is 1 to 14. In particular, thenumber of the methylene groups is more preferably 2 to 10.

Examples of a commercially available product of the compound having acarboxy group and a (meth)acryloyloxy group include LIGHT ACRYLATEHOAHH, HOAHH, HOHH, HOMPL, HOMPP, and HOA-MS (product names, allmanufactured by Kyoeisha Chemical Co., Ltd.).

The compounds having a hydrophilic group and a (meth)acryloyloxy groupmay be used alone or in combination of two or more kinds thereof.

Since the compound having a hydrophilic group and a (meth)acryloyloxygroup has high hydrophilicity, the compatibility with the compoundrepresented by Formula (I) is good, but there are combinations in whichcrystallization rarely occurs. In this case, a combination of a compoundhaving a hydrophilic group and a (meth)acryloyloxy group, thecrystallinity of which is not remarkably increased in the blended state,with the compound represented by Formula (I) is preferable. With this,the photo-alignment film becomes smooth and thus, an effect on thealignment regulating force becomes weaker.

The presence or absence of crystallization can be determined by, forexample, optical observation, spectroscopic analysis, scatteringexperiment, or the like.

The content of the binder component is preferably 10% by mass or more,more preferably 20% by mass or more, and still more preferably 30% bymass or more, with respect to the total solid content mass of thephoto-alignment film (composition for forming a photo-alignment film).In a case where the content of the binder component is 10% by mass ormore, there are advantages such as an ability of easy adjustment of therefractive index of the photo-alignment film, and an ability ofimproving adhesiveness to an adjacent layer and solvent resistance.

An upper limit value of the content of the binder component ispreferably 90% by mass or less, more preferably 85% by mass or less, andstill more preferably 80% by mass or less, with respect to the totalsolid content mass of the photo-alignment film (composition for forminga photo-alignment film) from the viewpoint that the alignment regulatingforce of the compound represented by Formula (I) included in thephoto-alignment film is further exhibited.

The composition for forming a photo-alignment film is preferablyproduced as a coating liquid. The solvent used for the production of thecoating liquid is not particularly limited, but a solvent in which aphotoactive compound is dissolved is usually used. Examples of thesolvent include alcohol-based solvents such as methanol and ethanol,diol-based solvents such as ethylene glycol, propylene glycol, and1,3-butanediol, ether-based solvents such as tetrahydrofuran,2-methoxyethanol, 2-butoxyethanol, 2-(2-ethoxyethoxy)ethanol, and2-(2-butoxyethoxy)ethanol, amide-based solvents such as 2-pyrrolidone,N-methylpyrrolidone, dimethylformamide, and dimethylacetamide,γ-butyrolactone, chlorobenzene, and dimethyl sulfoxide. The solvents maybe used alone or in combination of two or more kinds thereof.

The composition for forming a photo-alignment film is preferablyproduced as a coating liquid having a total solid content mass of 0.2%by mass or more, and more preferably produced as a coating liquid havinga total solid content mass of approximately 0.5% to 10% by mass.

As a method for applying the alignment polymer composition or thecomposition for forming a photo-alignment film onto a substrate (whichwill be described later), a known method including, for example, acoating method such as a spin coating method, an extrusion method, agravure coating method, a die-coating method, a bar coating method, andan applicator method, or a printing method such as a flexographic methodis employed. Incidentally, in a case where the production of apolarizing element is carried out by a continuous production method in aroll-to-roll mode, the gravure coating method, the die-coating method,or the like as the coating method, or the flexographic method asprinting method is preferable.

Anisotropic Light-Absorbing Film

The anisotropic light-absorbing film in the present invention is a filmformed using a dichroic substance and has a degree S of alignment of0.92 or more.

The degree S of alignment of the anisotropic light-absorbing film is0.92 or more, and more preferably 0.94 or more.

In order to enhance the degree of polarization as the polarizingelement, it is necessary to enhance the degree of alignment of thedichroic substance, but in a case where the degree of alignment isincreased, the refractive index anisotropy of the anisotropiclight-absorbing film is increased, and the interface reflection with anadjacent layer tends to be increased. Accordingly, in a case where thedegree of alignment is high as above, the present invention is moreeffective.

The anisotropic light-absorbing film may exhibit reverse wavelengthdispersibility. Exhibition of the reverse wavelength dispersibility ofthe anisotropic light-absorbing film means that an Re value becomesequal or higher as a measurement wavelength is increased in a case wherean in-plane retardation (Re) value at a specific wavelength (visiblelight range) is measured.

The anisotropic light-absorbing film exhibits reverse wavelengthdispersibility, and in a case where the ratio (n₄₅₀/n₅₅₀) of thealignment film is 1.0 or more, the internal reflection at an interfacebetween the anisotropic light-absorbing film and the alignment film canfurther be suppressed.

The thickness of the anisotropic light-absorbing film is preferably 100to 8,000 nm, and more preferably 300 to 5,000 nm. By making theanisotropic light-absorbing film into a thin film (having a thicknesswithin the range) as above, the flexibility of the polarizing elementcan be excellent.

The anisotropic light-absorbing film of the present invention ispreferably formed using a composition including a dichroic substance.

Dichroic Substance

The dichroic substance in the present invention is not particularlylimited as long as the degree S of alignment of the anisotropiclight-absorbing film can be set to 0.92 or more. Specific examplesthereof include those described in paragraphs [0067] to [0071] ofJP2013-228706A, paragraphs [0008] to [0026] of JP2013-227532A,paragraphs [0008] to [0015] of JP2013-209367A, paragraphs [0045] to[0058] of JP2013-014883A, paragraphs [0012] to [0029] of JP2013-109090A,paragraphs [0009] to [0017] of JP2013-101328A, paragraphs [0051] to[0065] of JP2013-037353A, paragraphs [0049] to [0073] of JP2012-063387A,paragraphs [0016] to [0018] of JP1999-305036A (JP-H11-305036A),paragraphs [0009] to [0011] of JP2001-133630A, paragraphs [0030] to[0169] of JP2011-215337A, paragraphs [0021] to [0075] of JP2010-106242A,paragraphs [0011] to [0025] of JP2010-215846A, paragraphs [0017] to[0069] of JP2011-048311A, paragraphs [0013] to [0133] of JP2011-213610A,paragraphs [0074] to [0246] of JP2011-237513A, paragraphs [0022] to[0080] of JP2015-001425, paragraphs [0005] to [0051] of JP2016-006502,paragraphs [0005] to [0041] of WO2016/060173A, paragraphs [0008] to[0062] of WO2016/136561A, paragraphs [0014] to [0033] of JP2016-044909,paragraphs [0014] to [0033] of JP2016-044910, paragraphs [0013] to[0037] of JP2016-095907, paragraphs [0014] to [0034] of JP2017-045296,and the like.

It is preferable that the dichroic substance includes a compoundrepresented by Formula (II) from the viewpoint that an anisotropiclight-absorbing film having a degree S of alignment of 0.92 or more iseasily obtained.

In Formula (II), R³¹, R³², R³³, R³⁴, and R³⁵ (hereinafter also simplyreferred to as “R³¹ to R³⁵” in some cases) each independently representa hydrogen atom or a substituent, R³⁶ and R³⁷ each independentlyrepresent a hydrogen atom or an alkyl group which may have asubstituent, Q³¹ represents an aromatic hydrocarbon group, an aromaticheterocyclic group, or a cyclohexane ring group, which may have asubstituent, L³¹ represents a divalent linking group, and A³¹ representsan oxygen atom or a sulfur atom. R³⁶, R³⁷, and Q³¹ may have a radicallypolymerizable group as a substituent.

The anisotropic light-absorbing film may include the dichroic substanceas it is, include a polymer of the dichroic substance, or both thereof.

The definitions of the substituent and the radically polymerizable groupin Formula (II) are the same as the substituent in Formula (I).

Examples of the aromatic hydrocarbon group represented by Q³¹ include anaryl group having 6 to 12 carbon atoms, and the aromatic hydrocarbongroup is preferably a phenyl group.

As the aromatic heterocyclic group represented by Q³¹, a group derivedfrom a monocyclic or bicyclic heterocycle is preferable. Examples of anatom constituting the aromatic heterocyclic group, other than a carbonatom, include a nitrogen atom, a sulfur atom, and an oxygen atom. In acase where the aromatic heterocyclic group has a plurality of atomsconstituting a ring other than carbon, these may be the same as ordifferent from each other. Specific examples of the aromaticheterocyclic group include a pyridyl group, a quinolyl group, anisoquinolyl group, a benzothiazolyl group, a phthalimido group, and athienothiazolyl group.

Examples of the divalent linking group represented by L³¹ include —O—,—(CH₂)_(g)—, —(CF₂)_(g)—, —Si(CH₃)₂—, —Si(CH₃)₂O)_(g)—,—(OSi(CH₃)₂)_(g)— (g represents an integer of 1 to 10), —N(Z)—,—C(Z)═C(Z′)—, —C(Z)═N—, —N═C(Z)—, —C(Z)₂—C(Z′)₂—, —C(O)—, —OC(O)—,—C(O)O—, —O—C(O)O—, —N(Z)C(O)—, —C(O)N(Z)—, —C(Z)═C(Z′)—C(O)O—,—O—C(O)—C(Z)═C(Z′)—, —C(Z)═N—, —N—C(Z)—, —C(Z)═C(Z′)—C(O)N(Z″)—,—N(Z″)—C(O)—C(Z)═C(Z′)—, —C(Z)═C(Z′)—C(O)—S—, —S—C(O)—C(Z)═C(Z′)—,—C(Z)═N—N═C(Z′)— (Z, Z′, and Z″ independently represent hydrogen, a C1to C4 alkyl group, a cycloalkyl group, an aryl group, a cyano group, ora halogen atom), —C≡C—, —N═N—, —S—, —S(O)—, —S(O)(O)—, —(O)S(O)O—,—O(O)S(O)O—, —SC(O)—, and —C(O)S—. Among these, —N═N— is preferable.

Specific examples of the compound represented by Formula (II) are shownbelow, but are not limited to the following specific examples.

The content of the dichroic substance is preferably 8% to 22% by mass,and more preferably 10% to 20% by mass with respect to the total solidcontent mass of the anisotropic light-absorbing film. In a case wherethe content of the dichroic substance is within the range, ananisotropic light-absorbing film having a high degree of alignment canbe obtained even in a case where the anisotropic light-absorbing film ismade into a thin film. With this, an anisotropic light-absorbing filmhaving excellent flexibility is easily obtained.

The dichroic substances may be used alone or in combination of two ormore kinds thereof. In a case where two or more kinds of the dichroicsubstances are included, the total amount thereof is preferably withinthe range.

In the present invention, it is preferable that the anisotropiclight-absorbing film is a film formed using a composition (hereinafteralso referred to as a “liquid crystalline composition”) including aliquid crystalline compound together with the above-mentioned dichroicsubstance for a reason that a dichroic substance can be aligned at ahigher degree of alignment while restraining the dichroic substance frombeing precipitated.

Liquid Crystalline Compound

As the liquid crystalline compound included in the liquid crystallinecomposition, both of a low-molecular liquid crystalline compound and ahigh-molecular liquid crystalline compound can be used.

Here, the “low-molecular liquid crystalline compound” refers to a liquidcrystalline compound having no repeating unit in the chemical structure.

In addition, the “high-molecular liquid crystalline compound” refers toa liquid crystalline compound having a repeating unit in the chemicalstructure.

Examples of the low-molecular liquid crystalline compound include thosedescribed in JP2013-228706A.

Examples of the high-molecular liquid crystalline compound include thethermotropic liquid crystalline polymers described in JP2011-237513A. Inaddition, the high-molecular liquid crystalline compound may have acrosslinkable group (for example, an acryloyl group and a methacryloylgroup) at the terminal.

In a case where the composition of the present invention contains aliquid crystalline compound, the content of the liquid crystallinecompound is preferably 70 to 95 parts by mass, and more preferably 70 to90 parts by mass with respect to 100 parts by mass of the total amountof the dichroic substance and the liquid crystalline compound in theliquid crystalline composition.

The liquid crystalline compounds may be used alone or in combination oftwo or more kinds thereof. In a case where two or more kinds of theliquid crystalline compounds are included, the total amount thereof ispreferably within the range.

Polymerization Initiator

The liquid crystalline composition may include a polymerizationinitiator.

The polymerization initiator is not particularly limited, but ispreferably a photosensitive compound, that is, a photopolymerizationinitiator.

As the photopolymerization initiator, various kinds of compounds can beused with no particular limitation. Examples of the photopolymerizationinitiator include α-carbonyl compounds (each of the specifications ofU.S. Pat. Nos. 2,367,661A and 2,367,670A), acyloin ethers (U.S. Pat. No.2,448,828A), aromatic acyloin compounds substituted by α-hydrocarbon(U.S. Pat. No. 2,722,512A), polynuclear quinone compounds (each of thespecifications of U.S. Pat. Nos. 3,046,127A and 2,951,758A),combinations of triarylimidazole dimers and p-aminophenyl ketones (U.S.Pat. No. 3,549,367A), acridine and phenazine compounds (JP1985-105667A(JP-S60-105667A) and U.S. Pat. No. 4,239,850A), oxadiazole compounds(U.S. Pat. No. 4,212,970A), and acylphosphine oxide compounds(JP1988-040799B (JP-S63-040799B), JP1993-029234B (JP-H05-029234B),JP1998-095788A (JP-H10-095788A), and JP1998-029997A (JP-H10-029997A)).

A commercially available product can also be used as such aphotopolymerization initiator, and examples thereof include IRGACURE(hereinafter also simply referred to as “Irg”)-184, IRGACURE-907,IRGACURE-369, IRGACURE-651, IRGACURE-819, IRGACURE-OXE-01, andIRGACURE-OXE-02, manufactured by BASF.

In a case where the composition of the present invention contains apolymerization initiator, the content of the polymerization initiator ispreferably 0.01 to 30 parts by mass, and more preferably 0.1 to 15 partsby mass with respect to 100 parts by mass of the total amount of thedichroic substance and the liquid crystalline compound in the liquidcrystalline composition. In a case where the content of thepolymerization initiator is 0.01 parts by mass or more, the durabilityof the anisotropic light-absorbing film becomes good, whereas in a casewhere the content of the polymerization initiator is 30 parts by mass orless, the degree of alignment of the anisotropic light-absorbing filmbecomes better.

The polymerization initiators may be used alone or in combination of twoor more kinds thereof. In a case where two or more kinds of thepolymerization initiators are included, the total amount thereof ispreferably within the range.

Interface Modifier

The liquid crystalline composition preferably includes an interfacemodifier. By incorporation of the interface modifier, effects that thesmoothness of the coating surface is improved; the degree of alignmentis further improved or cissing and unevenness are suppressed; and thein-plane uniformity is improved are anticipated.

As the interface modifier, a material having a dichroic substance and aliquid crystalline compound horizontal on the coating surface side ispreferable, and the compounds (horizontal alignment agents) described inparagraphs [0253] to [0293] of JP2011-237513A can be used.

In a case where the anisotropic light-absorbing film used in the presentinvention contains an interface modifier, the content of the interfacemodifier is preferably 0.001 to 5 parts by mass, and more preferably0.01 to 3 parts by mass with respect to 100 parts by mass of the totalamount of the dichroic substance and the liquid crystalline compound inthe liquid crystalline composition.

The interface modifiers may be used alone or in combination of two ormore kinds thereof. In a case where two or more kinds of the interfacemodifier are included, the total amount thereof is preferably within therange.

Solvent

The liquid crystalline composition preferably includes a solvent fromthe viewpoint of workability or the like.

Examples of the solvent include organic solvents such as ketones (forexample, acetone, 2-butanone, methyl isobutyl ketone, cyclopentanone,and cyclohexanone), ethers (for example, dioxane, tetrahydrofuran, andcyclopentyl methyl ether), aliphatic hydrocarbons (for example, hexane),alicyclic hydrocarbons (for example, cyclohexane), aromatic hydrocarbons(for example, benzene, toluene, xylene, and trimethylbenzene),halogenated carbons (for example, dichloromethane, trichloromethane(chloroform), dichloroethane, dichlorobenzene, and chlorotoluene),esters (for example, methyl acetate, ethyl acetate, and butyl acetate),alcohols (for example, ethanol, isopropanol, butanol, and cyclohexanol),cellosolves (for example, methyl cellosolve, ethyl cellosolve, and1,2-dimethoxyethane), cellosolve acetates, sulfoxides (for example,dimethyl sulfoxide), amides (for example, dimethylformamide anddimethylacetamide), and heterocyclic compounds (for example, pyridine),and water. These solvents may be used alone or in combination of two ormore kinds thereof.

Among these solvents, the organic solvents are preferably used, and thehalogenated carbons or the ketones are more preferably used.

In a case where the liquid crystalline composition includes a solvent,the content of the solvent is preferably 80% to 99% by mass, morepreferably 83% to 97% by mass, and particularly preferably 85% to 95% bymass with respect to the total mass of the liquid crystallinecomposition.

The solvents may be used alone or in combination of two or more kindsthereof. In a ease where two or more kinds of the solvents are included,the total amount thereof is preferably within the range.

Substrate

The polarizing element of the embodiment of the present invention mayfurther have a substrate.

In a case where the substrate is a substrate used for the creation of anoptical film or the like, it is not particularly limited. The substratemay have flexibility and peelability, as desired.

An aspect in which the alignment film and the anisotropiclight-absorbing film are provided in this order on a substrate, and thesubstrate is disposed on the side of the alignment film opposite to theanisotropic light-absorbing film is also available.

The substrate is preferably a substrate having transparency with respectto visible light.

The transparency refers to characteristics that a transmittance withrespect to rays at a wavelength from 380 to 780 nm is 80% or more.Specific examples of the substrate include a glass substrate and aplastic substrate, and the substrate is preferably the plasticsubstrate. Examples of a plastic constituting the plastic substrateinclude plastics including, for example, polyolefins such aspolyethylene, polypropylene, and a norbornene-based polymer; cyclicolefin-based resins; polyvinyl alcohol; polyethylene terephthalate;polymethacrylic acid esters; polyacrylic acid esters; cellulose esterssuch as triacetyl cellulose, diacetyl cellulose and cellulose acetatepropionate; polyethylene naphthalate; polycarbonates; polysulfones;polyether sulfones; polyether ketones; polyphenylene sulfides; andpolyphenylene oxides and polyimides. Among these, cellulose esters,cyclic olefin-based resins, polyethylene terephthalate, polymethacrylicacid esters, or polyimides are particularly preferable from theviewpoint that they are easily available from the market or thetransparency is excellent.

An alignment film formed using a modified polyvinyl alcohol or the likemay be formed on a substrate, and the alignment film in the presentinvention may be formed on the alignment film formed using a modifiedpolyvinyl alcohol or the like.

It is preferable that the thickness of the substrate is smaller to anextent such that the strength and the workability are maintained fromthe viewpoints that the smaller thickness results in a weight to anextent such that practical handling is allowed and that sufficienttransparency can be secured.

The thickness of the glass substrate is, but not limited to, preferably100 to 3,000 μm, and more preferably 100 to 1,000 μm.

The thickness of the plastic substrate is, but not limited to,preferably 5 to 300 μm, and more preferably 5 to 200 μm.

In a case where the polarizing element of the embodiment of the presentinvention is used as a circularly polarizing plate which will bedescribed later (in particular, a case where it is used as a circularlypolarizing plate in applications of mobile devices), the thickness ofthe substrate is preferably approximately 5 to 100 μm.

Refractive Index Difference

In a case where the refractive index of the anisotropic, light-absorbingfilm is defined as Nx₅₅₀ and the refractive index of the alignment filmis defined as nx₅₅₀ in a direction in which an in-plane refractive indexof the anisotropic light-absorbing film at a wavelength of 550 nm ismaximized, and the refractive index of the anisotropic light-absorbingfilm is defined as Ny₅₅₀ and the refractive index of the alignment filmis defined as ny₅₅₀ in a direction in-plane perpendicular to thedirection in which the in-plane refractive index is maximized in theplane of the anisotropic light-absorbing film, it is preferable thatFormula (1) is satisfied.|Nx ₅₅₀ −nx ₅₅₀ |+|Ny ₅₅₀ −ny ₅₅₀|<0.3  Formula (1)

The light at a wavelength of 550 nm is a light at a wavelength such thatthe light is easily visibly recognized to the human eyes. With this, ina case where Formula (1) is satisfied even though the degree ofalignment of the anisotropic light-absorbing film is high and theanisotropy of the refractive index is high, the reflected light is moreeasily visibly recognized, and therefore, the interface reflectionbetween the anisotropic light-absorbing film and the alignment film canfurther be suppressed. Thus, a polarizing element satisfying Formula (1)can exhibit a more excellent antireflection function as applied to animage display device.

The value of |Nx₅₅₀ −nx ₅₅₀|+|Ny₅₅₀−ny₅₅₀| is less than 0.3, and fromthe viewpoint that the effect is further exhibited, the value ispreferably 0.2 or less.

Circularly Polarizing Plate

The circularly polarizing plate of an embodiment of the presentinvention has the above-mentioned polarizing element and a ¼ wavelengthplate.

¼ Wavelength Plate

The ¼ wavelength plate used in the present invention is not particularlylimited as long as it is usually used, and a polymer film or a ¼wavelength plate created from a liquid crystalline compound can be used.Examples thereof include PURE-ACE WR (manufactured by Teijin Limited).

In addition, the above-mentioned substrate may also serve as a ¼wavelength plate.

As the ¼ wavelength plate, a ¼ wavelength plate exhibiting reversedispersibility is preferably used. In addition, a plurality of layersmay be laminated to form a ¼ wavelength plate in combination.

The ¼ wavelength plate and the polarizing element of the embodiment ofthe present invention may be provided to be in contact with each other,and another layer may be provided between the ¼ wavelength plate and thepolarizing element of the embodiment of the present invention. Examplesof such a layer include a pressure sensitive adhesive layer or adhesivelayer for securing adhesiveness, and a barrier layer.

Barrier Layer

A barrier layer may be provided between the polarizing element of theembodiment of the present invention and the ¼ wavelength plate.Incidentally, in a case where a layer (for example, a pressure sensitiveadhesive layer and an adhesive layer) other than the barrier layer isprovided the polarizing element of the embodiment of the presentinvention and the ¼ wavelength plate, the barrier layer may be provided,for example, between the polarizing element of the embodiment of thepresent invention and another layer.

The harrier layer is also called a gas shielding layer (oxygen shieldinglayer), and has a function of protecting the polarizing element of theembodiment of the present invention from a gas such as oxygen in theair, moisture, the compounds included in an adjacent layer.

With regard to the barrier layer, reference can be made to, for example,the descriptions in paragraphs [0014] to [0054] of JP2014-159124A,paragraphs [0042] to [0075] of JP2017-121721A, paragraphs [0045] to[0054] of JP2017-115076A, paragraphs [0010] to [0061] of JP2012-213938A,or paragraphs [0021] to [0031] of JP2005-169994A.

Image Display Device

The image display device of an embodiment of the present invention hasthe above-mentioned anisotropic light-absorbing film or circularlypolarizing plate, and an image display element. In the image displaydevice, the anisotropic light-absorbing film or circularly polarizingplate preferably functions as an antireflection layer.

Image Display Element

The image display element is not particularly limited and examplesthereof include a liquid crystal cell, an organic electroluminescent(hereinafter abbreviated as “EL”) display panel, and a plasma displaypanel.

Among these, the liquid crystal cell or the organic EL display panel ispreferable. That is, as the image display device of the embodiment ofthe present invention, a liquid crystal display device using a liquidcrystal cell as an image display element, or an organic EL displaydevice using an organic EL display panel as an image display element ispreferable.

Liquid Crystal Cell

The liquid crystal cell used for the liquid crystal display device ispreferably in a vertical alignment (VA) mode, an optically compensatedbend (OCB) mode, an in-plane-switching (IPS) mode, or a twisted nematic(TN) mode, but is not limited thereto.

In a liquid crystal cell in the TN mode, rod-like liquid crystallinemolecules are substantially horizontally aligned with no application ofa voltage, and twist-aligned by 60° to 120°. The liquid crystal cell inthe TN mode is most frequently used as a color thin film transistor(TFT) liquid crystal display device, and is described in manyliteratures.

In a liquid crystal cell in the VA mode, rod-like liquid crystallinemolecules are substantially vertically aligned with no application of avoltage. The liquid crystal cell in the VA mode includes (1) anarrowly-defined liquid crystal cell in the VA mode in which rod-likeliquid crystalline molecules are substantially vertically aligned withno application of a voltage, and are substantially horizontally alignedwith the application of a voltage (described in JP1990-176625A(JP-H02-176625A)), (2) a liquid crystal cell (in the MVA mode) in whichthe VA mode is made into multi-domains in order to expand the viewingangle (described in SID97, Digest of tech. Papers (proceedings) 28(1997) 845), (3) an liquid crystal cell in a mode (the n-ASM mode) inwhich rod-like liquid crystalline molecules are substantially verticallyaligned with no application of a voltage, and are twistedly aligned inmulti-domains with the application of a voltage (described in theproceedings 58 and 59 of Japanese Liquid Crystal Conference (1998)), and(4) a liquid crystal cell in the SURVIVAL mode (announced at LCDinternal 98). In addition, the liquid crystal cell in the VA mode may beany one of a patterned vertical alignment (PVA) type, an opticalalignment type, and a polymer-sustained alignment (PSA) type. Details ofthese modes are described in JP2006-215326A and JP2008-538819A.

In a liquid crystal cell in the IPS mode, rod-like liquid crystallinemolecules are substantially aligned in parallel to a substrate, and theliquid crystalline molecules respond in a planar manner with theapplication of an electric field in parallel to a substrate surface. TheIPS mode displays a black image in a state in which no electric field isapplied thereto, and the absorption axes of a pair of upper and lowerpolarizing plates are perpendicular to each other. A method of improvingthe viewing angle by reducing light leakage caused when a black image isdisplayed in an oblique direction using an optical compensation sheet isdisclosed by JP1998-054982A (JP-H10-054982A), JP1999-202323A(JP-H11-202323A), JP1997-292522A (JP-H9-292522A), JP1999-133408A(JP-H11-133408A), JP1999-305217A (JP-H11-305217A), JP1998-307291A(JP-H10-307291A), and the like.

Organic EL Display Device

As an organic EL display device as an example of the image displaydevice of the embodiment of the present invention, an aspect in which ithas an anisotropic light-absorbing film, a ¼ wavelength plate, and anorganic EL display panel in this order from the visibly recognized sidecan be suitably mentioned.

An aspect in which the organic EL display panel has the above-describedcircularly polarizing plate having a ¼ wavelength plate and an organicEL display panel in this order from the visibly recognized side is moresuitable. In this case, the circularly polarizing plate has a substrate,an alignment film, an anisotropic light-absorbing film, and a ¼wavelength plate disposed in this order from the visibly recognizedside.

In addition, the organic EL display panel is a display panel configuredusing an organic EL element in which an organic light emitting layer(organic electroluminescence layer) is interposed between electrodes(between a cathode and an anode). The configuration of the organic ELdisplay panel is not particularly limited, and a known configuration isemployed.

EXAMPLES

Hereinafter, the present invention will be described in more detailswith reference to Examples. The materials, the amounts to materialsused, the ratios, the treatment details, the treatment procedure, or thelike shown in the following Examples can be modified as appropriatewhile not departing from the spirit of the present invention. Therefore,the scope of the present invention will not be restrictively interpretedby the following Examples.

Creation of Alignment Film 1

To 1.0 part by mass of a photo-alignment material E-1 having thefollowing structure were added 41.6 parts by mass of butoxyethanol. 41.6parts by mass of dipropylene glycol monomethyl, and 15.8 parts by massof pure water, and the obtained solution was pressure-filtered through a0.45-μm membrane filter to create a coating liquid 1 for aphoto-alignment film. The obtained coating liquid 1 for aphoto-alignment film was applied onto a polyethylene terephthalate (PET)substrate and dried at 60° C. for 1 minute. The obtained applied filmwas irradiated with linear polarized ultraviolet rays (an illuminance of4.5 mW, an irradiation amount of 500 mJ/cm²) using a polarizedultraviolet exposure device to create an alignment film 1. Variousrefractive indices and film thicknesses of the obtained alignment film 1are shown in Table 1.

Creation of Alignment Film 2

To 0.67 parts by mass of the photo-alignment material E-1 were added0.33 parts by mass of DENACOL ACRYLATE DA-212 manufactured by NagaseChemteX Corporation, 41.6 parts by mass of butoxyethanol, 41.6 parts bymass of dipropylene glycol monomethyl, and 15.8 parts by mass of purewater, and the obtained solution was pressure-filtered through a 0.45 nmmembrane filter to create a coating liquid 2 for a photo-alignment film.The obtained coating liquid for a photo-alignment film was applied ontoa PET substrate and dried at 60° C. for 1 minute. The obtained appliedfilm was irradiated with linear polarized ultraviolet rays (anilluminance of 4.5 mW, an irradiation amount of 500 mJ/cm²) using apolarized ultraviolet exposure device to create an alignment film 2.Various refractive indices and film thicknesses of the obtainedalignment film 2 are shown in Table 1.

Creation of Alignment Films 3 to 8 and 14

Alignment films 3 to 8 and 14 were created by the same method as for thealignment film 1, except that the contents of the photo-alignmentmaterial E-1 and DENACOL ACRYLATE DA-212 manufactured by Nagase ChemteXCorporation and the irradiation amount of the linear polarizedultraviolet rays were changed as shown in Table 1 below. Variousrefractive indices and film thicknesses of each of the alignment filmsare shown in Table 1.

Creation of Alignment Film 9

An alignment film coating liquid 9 having the following composition wascontinuously applied onto a PET substrate with a wire bar of #8. Theresultant was dried with hot air at 100° C. for 2 minutes to obtain analignment film having a thickness of 0.8 μm. Further, a modifiedpolyvinyl alcohol (modified PVA) was added into an alignment filmcoating liquid such that the concentration of the solid content became4% by mass. The created alignment film was subjected to a rubbingtreatment to create an alignment film 9. Various refractive indices andfilm thicknesses of the obtained alignment film 9 are shown in Table 1.

Composition of Alignment Film Coating Liquid 9

The following modified polyvinyl alcohol

Water 70 parts by mass Methanol 30 parts by mass

Creation of Alignment Film 10 Synthesis of Polymer C-2

Into a reaction vessel provided with a stirrer, a thermometer, adripping funnel, and a reflux cooling pipe were introduced 100.0 partsby mass of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 500 parts bymass of methyl isobutyl ketone, and 10.0 parts by mass of triethylamine,and the mixture was stirred at room temperature. Next, 100 parts by massof deionized water was added dropwise to the obtained mixture for 30minutes with a dripping funnel, and then allowed to undergo a reactionat 80° C. for 6 hours while mixing the mixture under reflux. Aftercompletion of the reaction, the organic phase was extracted and washeduntil water after the washing became neutral with a 0.2%-by-mass aqueousammonium nitrate solution. Thereafter, the solvent and water weredistilled off under reduced pressure from the obtained organic phase toobtain a polyorganosiloxane having an epoxy group as a viscoustransparent liquid.

The polyorganosiloxane having an epoxy group was subjected to ¹H-NuclearMagnetic Resonance (NMR) analysis, and thus, it was confirmed that peaksbased on an oxiranyl group around a chemical shift (δ)=3.2 ppm wereobtained as per theoretical strength, and a side reaction of the epoxygroup did not occur during the reaction. The weight-average molecularweight Mw and the epoxy equivalent of the polyorganosiloxane having anepoxy group were 2,200 and 186 g/mole, respectively.

Next, into a 100-mL three-neck flask were introduced 10.1 parts by massof the polyorganosiloxane having an epoxy group obtained above, 0.5parts by mass of an acryloyl group-containing carboxylic acid(manufactured by Toagosei Co., Ltd., product name “ARONIX M-5300”,ω-carboxypolycaprolactone acrylate (a degree of polymerization of n≅2)),20 parts by mass of butyl acetate, 1.5 parts by mass of a cinnamic acidderivative obtained by the method of Synthesis Example 1 ofJP2015-026050A, and 0.3 parts by mass of tetrabutylammonium bromide, andthe obtained mixture was stirred at 90° C. for 12 hours. After stirring,the mixture was diluted with butyl acetate in the same amount (mass) asthat of the obtained mixture, and the diluted mixture was washed withwater three times. An operation in which the obtained mixture wasconcentrated and diluted with butyl acetate was repeated twice tofinally obtain a solution including polyorganosiloxane (the followingpolymer C-2) having a photo-alignment group. The weight-averagemolecular weight Mw of the polymer C-2 was 9,000. In addition, as aresult of ¹H-NMR analysis, the amount of the components having acinnamate group in the polymer C-2 was 23.7% by mass.

Production of Composition 10 for Forming Alignment Layer

The following components were mixed to produce a composition 10 forforming an alignment layer.

Polymer C-2 10.67 parts by mass Low-molecular compound R-1 5.17 parts bymass Additive (B-1) 0.53 parts by mass Butyl acetate 8,287.37 parts bymass Propylene glycol monomethyl ether acetate 2,071.85 parts by mass

Additive (B-1): TA-60B manufactured by San-Apro Limited (refer to thefollowing structural formula)

The composition 10 for forming an alignment layer was applied onto a PETsubstrate by a spin coating method, and a support having the composition10 for forming an alignment layer applied thereon was dried in a hotplate at 80° C. for 5 minutes to remove the solvent, thereby forming acoating film.

The obtained coating film was irradiated with polarized ultraviolet rays(25 mJ/cm², ultra-high-pressure mercury lamp) to create an alignmentfilm 10. Various refractive indices and film thicknesses of the obtainedalignment film 10 are shown in Table 1.

Creation of Alignment Film 11

A composition 11 for forming an alignment film was continuously appliedonto a PET substrate after drying, using a bar of #4, and the appliedcomposition 11 for forming an alignment film was dried at 80° C. for 15minutes and then heated at 250° C. for 1 hour to form an applied film onthe PET substrate.

The obtained applied film was once irradiated with polarized ultravioletrays (1,000 mJ/cm², ultra-high-pressure mercury lamp) to create analignment film 11 on the PET substrate. Various refractive indices andfilm thicknesses of the obtained alignment film 11 are shown in Table 1.

Composition of composition 11 for forming alignment film SE-130 (productname, manufactured by Nissan 2.0 parts by mass Chemical Industries,Ltd., polyimide compound) N-Methylpyrrolidone 98.0 parts by mass

Creation of Alignment Film 12

An alignment film 12 was created by the same method as for the alignmentfilm 9, except that a triacetyl cellulose (TAC) substrate (TG40,manufactured by FUJIFILM Corporation) having a thickness of 40 μm wasused as the substrate. Various refractive indices and film thicknessesof the alignment film 12 are shown in Table 1.

Creation of Alignment Film 13

The coating liquid 1 for a photo-alignment film was applied onto thealignment film 12 and dried at 60° C. for 1 minute. The obtained appliedfilm was irradiated with linear polarized ultraviolet rays (anilluminance of 4.5 mW, an irradiation amount of 1,000 mJ/cm²) using apolarized ultraviolet exposure device to create an alignment film 13.Various refractive indices and film thicknesses of the obtainedalignment film 13 are shown in Table 1.

Example 101

The following liquid crystalline composition 1 was continuously appliedonto the obtained alignment film 1 using a wire bar of #11 to form anapplied film 101.

The applied film 1 was heated at 140° C. for 90 seconds and was cooledto room temperature. Subsequently, the applied film 1 was heated at 80°C. for 60 seconds and cooled again to room temperature. Thereafter, thefilm was irradiated under an irradiation condition of an illuminance of28 mW/cm² for 60 seconds using a high-pressure mercury lamp to create ananisotropic light-absorbing film (a thickness of 2,000 nm) on thealignment film 1. In this manner, a polarizing element of Example 101was created. The degree of alignment of the obtained polarizing element101 is shown in Table 1.

In addition, the anisotropic light-absorbing film was peeled from thepolarizing element of Example 101, and the degree S of alignment wasmeasured by the above-mentioned method. The degree S of alignment of theanisotropic light-absorbing film is shown in Table 1.

Composition of liquid crystalline composition 1 Yellow azo coloringagent Y-1 7.1 parts by mass Cyan azo coloring agent C-1 9.1 parts bymass High-molecular liquid crystal compound P-1 101.1 parts by massPolymerization initiator IRGACURE 819 1.0 part by mass (manufactured byBASF) Interface modifier F-1 0.3 parts by mass Cyclopentanone 617.0parts by mass Tetrahydrofuran 264.4 parts by mass

Yellow Azo Coloring Agent Y-1

Cyan Azo Coloring Agent C-1

High-molecular liquid crystal compound P-1 (the numerical value in therepeating unit represents % by mole of each repeating unit with respectto all the repeating units in the high-molecular liquid crystallinecompound P-1)

Interface modifier F-1 (the numerical value in the repeating unitrepresents % by mole of each repeating unit with respect to all therepeating units in the interface modifier F-1)

Examples 102 to 113 and Comparative Examples 201 to 204

Anisotropic light-absorbing films were created on the alignment films 2to 14 by the same method as in Example 101, except that the blend ratioof two kinds of dichroic substances was set to be the same as in Example101 and only the solid fractions of the dichroic substances were changedas in Table 1. In this manner, polarizing elements of Examples 102 to113 and Comparative Examples 201 to 204 were created.

In addition, the anisotropic light-absorbing film was peeled from thepolarizing element of each of Examples and Comparative Examples and thedegree S of alignment was measured by the above-mentioned method. Thedegree S of alignment of the anisotropic light-absorbing film is shownin Table 1.

Example 114

The following composition 1 for forming an oxygen shielding layer wascontinuously applied onto the anisotropic light-absorbing film ofExample 113 with a wire bar of #17 and dried at 60° C. for 5 minutes tocreate a polarizing element of Example 114 in which the oxygen shieldinglayer was formed on the anisotropic light-absorbing film.

In addition, the anisotropic light-absorbing film was peeled from thepolarizing element of Example 114 and the degree S of alignment wasmeasured by the above-mentioned method. The degree S of alignment of theanisotropic light-absorbing film is shown in Table 1.

Composition 1 for forming oxygen shielding layer Modified polyvinylalcohol 7 parts by mass Water 72 parts by mass Methanol 21 parts by mass

Example 115

The following composition 2 for forming an oxygen shielding layer wascontinuously applied onto the anisotropic light-absorbing film ofExample 113 with a wire bar of #5 and dried at 60° C. for 5 minutes tocreate a polarizing element of Example 115 in which the oxygen shieldinglayer was formed on the anisotropic light-absorbing film.

In addition, the anisotropic light-absorbing film was peeled from thepolarizing element of Example 115 and the degree S of alignment wasmeasured by the above-mentioned method. The degree S of alignment of theanisotropic light-absorbing film is shown in Table 1.

Composition 2 for forming oxygen shielding layer Compound BA-1 (below)29 parts by mass Polymerization initiator IRGACURE 819 1 part by mass(manufactured by BASF) Ethanol 70 parts by mass

Creation of Circularly Polarizing Plate

A pressure sensitive adhesive (SK-2057, manufactured by Soken Chemical &Engineering Co., Ltd.) was applied onto the side of the anisotropiclight-absorbing film of the polarizing element created above (on theside of the oxygen shielding layer in a case where the oxygen shieldinglayer was formed) to form a pressure sensitive adhesive layer, andPURE-ACE WR (manufactured by Teijin Limited) as a ¼ wavelength plate wasadhered thereonto to create a circularly polarizing plate.

GALAXY S5 manufactured by SAMSUNG, having an organic EL panel (organicEL display element) installed therein, was disintegrated, the touchpanel to which the circularly polarizing plate was adhered was peeledfrom the organic EL display device, the circularly polarizing plate wasfurther peeled from the touch panel, and the organic EL display element,the touch panel, and the circularly polarizing plate were each isolated.Subsequently, the isolated touch panel was adhered again to the organicEL display element, which was further adhered to the touch panel suchthat air did not enter the created circularly polarizing plate, therebycreate an organic EL display device.

Evaluation of Display Performance

With regard to the organic EL display device created, visibility anddisplay quality were evaluated under illumination. The display screen ofthe display device was taken as a black display and the reflected lightwas observed upon irradiation of fluorescent light from the front and ata polar angle of 45 degrees. The display performance was evaluated onthe basis of the following criteria. The evaluation results are shown inTable 1.

A: The light is black and the color is not visibly recognized at all.

B: Slight coloration is visibly recognized but the reflectance is verylow.

C: Slight coloration is visibly recognized but the reflectance is low.

D: Slight coloration is visibly recognized and the reflectance is high.

E: Clear coloration is visibly recognized and the reflectance is high.

TABLE 1 Alignment film Material of Binder alignment film componentAverage Average Parts by Parts by UV Irradiation refractive refractiveSubstrate Type Type mass Type mass amount mJ/cm² index n_(ave) indexn₅₅₀ Example 101 PET Alignment film 1 E-1 1.0 — — 500 1.78 1.73 Example102 PET Alignment film 11 SE-130 — — — 1,000 1.68 1.64 Example 103 PETAlignment film 2 E-1 0.7 DA-212 0.3 500 1.69 1.65 Example 104 PETAlignment film 3 E-1 0.5 DA-212 0.5 500 1.65 1.61 Example 105 PETAlignment film 4 E-1 0.3 DA-212 0.7 500 1.62 1.58 Example 106 PETAlignment film 5 E-1 1.0 — — 300 1.78 1.73 Example 107 PET Alignmentfilm 6 E-1 1.0 — — 1,000 1.78 1.73 Example 108 PET Alignment film 3 E-10.5 DA-212 0.5 500 1.65 1.61 Example 109 PET Alignment film 3 E-1 0.5DA-212 0.5 500 1.65 1.61 Example 110 PET Alignment film 14 E-1 0.5DA-212 0.5 1,000 1.65 1.61 Example 111 PET Alignment film 7 E-1 1.0 — —100 1.78 1.73 Example 112 PET Alignment film 8 E-1 1.0 — — 3,000 1.781.73 Example 113 TG40 Alignment film 13 E-1 1.0 — — 1,000 1.78 1.73Example 114 TG40 Alignment film 13 E-1 1.0 — — 1,000 1.78 1.73 Example115 TG40 Alignment film 13 E-1 1.0 — — 1,000 1.78 1.73 Comparative PETAlignment film 9 Modified PVA — — — — 1.52 1.52 Example 201 ComparativePET Alignment film 10 C-2 — — — 25 1.51 1.52 Example 202 Comparative PETAlignment film 7 E-1 1.0 — — 50 1.78 1.73 Example 203 Comparative TG40Alignment film 12 Modified PVA — — — — 1.51 1.52 Example 204 Anisotropiclight-absorbing film Alignment film Amount of Solid Refractive Filmcontent of |Nx₅₅₀ − Oxygen Ratio index thickness dichroic Degree S ofnx₅₅₀| + |Ny₅₅₀ − shielding Display (n₄₅₀/n₅₅₀) anisotropy Δn (nm)substance alignment ny₅₅₀| layer performance Example 101 1.09 0.30 2714% 0.95 0.11 — A Example 102 1.09 0.10 50 14% 0.95 0.18 — A Example 1031.08 0.21 45 10% 0.93 0.02 — A Example 104 1.07 0.18 55 14% 0.95 0.12 —A Example 105 1.02 0.16 70 14% 0.94 0.17 — A Example 106 1.09 0.22 2414% 0.93 0.15 — A Example 107 1.09 0.36 25 14% 0.95 0.11 — A Example 1081.07 0.18 55 21% 0.95 0.18 — B Example 109 1.07 0.18 55 8% 0.93 0.08 — AExample 110 1.07 0.24 42 14% 0.94 0.11 — A Example 111 1.09 0.03 22 14%0.92 0.22 — B Example 112 1.09 0.46 25 14% 0.95 0.32 — B Example 1131.09 0.30 23 14% 0.95 0.14 — A Example 114 1.09 0.30 23 14% 0.95 0.14Modified A PVA Example 115 1.09 0.30 23 14% 0.95 0.14 BA-1 A Comparative1.03 0.00 800 14% 0.94 0.26 — D Example 201 Comparative 1.01 0.02 80 13%0.93 0.26 — D Example 202 Comparative 1.09 0.06 55 5% 0.88 0.32 — DExample 203 Comparative 1.03 0.00 800 14% 0.94 0.26 — D Example 204

From Table 1, it was confirmed that in a case where the degree ofalignment of the anisotropic light-absorbing film is 0.92 or more andthe average refractive index n_(ave) of the alignment film is in therange of 1.55 to 2.0, the display performance of the image displaydevice is excellent (Examples 101 to 115).

On the other hand, it was confirmed that in a case where the degree ofalignment of the anisotropic light-absorbing film is less than 0.92 andthe average refractive index n_(ave) of the alignment film is out of therange of 1.55 to 2.0, the display performance of the image displaydevice is deteriorated (Comparative Examples 201 to 204).

Creation of λ/4 Phase Difference Film 1 Production of Composition forPhoto-Alignment Film

The same composition as the composition 10 for forming an alignment filmused for the formation of the alignment film 10 was produced.

The coating liquid for an optically anisotropic layer having thefollowing composition was produced.

Coating liquid for optically anisotropic layer Liquid crystallinecompound L-3 42.00 parts by mass The following liquid crystallinecompound L-4 42.00 parts by mass The following polymerizable compoundA-1 16.00 parts by mass The following low-molecular compound B2 6.00parts by mass The following polymerization initiator S-1 0.50 parts bymass (oxime-type) The following leveling agent. G-1 0.20 parts by massHISOLVE MTEM (manufactured by TOHO 2.00 parts by mass Chemical IndustryCo., Ltd.) NKester A-200 (manufactured by Shin Nakamura 1.00 part bymass Chemical Co., Ltd.) Methyl ethyl ketone 424.8 parts by mass

In addition, a group adjacent to the acryloyloxy group of each of thefollowing liquid crystalline compounds L-3 and L-4 represents apropylene group (a group in which is a methyl group is substituted withan ethylene group), and the following liquid crystalline compounds L-3and L-4 represent a mixture having different positions of the methylgroups.

Creation of Cellulose Acylate Film 1 Creation of Core Layer CelluloseAcylate Dope

The following composition was introduced into a mixing tank and stirredto dissolve the respective components, thereby producing a celluloseacetate solution for use as a core layer cellulose acylate dope.

Core layer cellulose acylate dope Cellulose acetate having degree ofacetyl 100 parts by mass substitution of 2.88 Polyester compound Bdescribed in Examples of 12 parts by mass JP2015-227955A The followingcompound F 2 parts by mass Methylene chloride (first solvent) 430 partsby mass Methanol (second solvent) 64 parts by mass

Creation of Outer Layer Cellulose Acylate Dope

To 90 parts by mass of the core layer cellulose acylate dope was added10 parts by mass of the following matting agent solution to produce acellulose acetate solution for use as an outer layer cellulose acylatedope.

Matting agent solution Silica particle having average particle size of20 nm 2 parts by mass (AEROSIL R972, manufactured by Nippon Aerosil Co.,Ltd.) Methylene chloride (first solvent) 76 parts by mass Methanol(second solvent) 11 parts by mass The above core layer cellulose acylatedope 1 part by mass

Creation of Cellulose Acylate Film 1

The core layer cellulose acylate dope and the outer layer celluloseacylate dope were filtered through a filter paper having an average porediameter of 34 μm and a sintered metal filter having an average porediameter of 10 μm, and then three layers of the core layer celluloseacylate dope and the outer layer cellulose acylate dope on both sidesthereof were cast on a drum at 20° C. from the casting ports at the sametime (band casting machine).

Subsequently, the film was peeled in the state where the solvent contentreadied approximately 20% by mass, the both terminals of the film in thewidth direction were fixed with tenter clips, and the film was driedwhile being stretched at a stretching ratio of 1.1 times in the crossdirection.

Thereafter, the film was transported between rolls in a heat treatmentdevice and further dried to create a cellulose acylate film 1 having athickness of 40 μm. The in-plane retardation of the obtained celluloseacylate film 1 was 0 nm.

Creation of λ/4 Phase Difference Film 1

The composition for the photo-alignment film produced in advance wasapplied onto a surface on one side of the created cellulose acylate film1.

After the application, the film was dried in a hot plate at 120° C. for1 minute to remove the solvent, thereby forming a photoisomerizationcomposition layer having a thickness of 0.3 μm. The obtainedphotoisomerization composition layer was irradiated with polarizedultraviolet rays (10 mJ/cm², using an ultra-high-pressure mercury lamp)to form a photo-alignment film.

Subsequently, the coating liquid for an optically anisotropic layerproduced in advance was applied onto the photo-alignment film with a barcoater to form a composition layer. The formed composition layer wasfirst heated in a hot plate to 110° C. and then cooled 60° C. tostabilize the alignment. Thereafter, while keeping the temperature at60° C., the alignment was fixed by irradiation with ultraviolet rays(500 mJ/cm², using an ultra-high-pressure mercury lamp) in a nitrogenatmosphere (an oxygen concentration of 100 ppm) to form an opticallyanisotropic layer having a thickness of 2.3 μm, and thus, a λ/4 phasedifference film 1 was created.

The in-plane retardation of the obtained λ/4 phase difference film 1 was140 nm.

Creation of Positive C Plate Film 2

A triacetyl cellulose film “Z-TAC” (manufactured by FUJIFILMCorporation) was used as a temporary support (which was referred to as acellulose acylate film 2). The cellulose acylate film 2 was allowed topass through a dielectric heating roll at a temperature of 60° C., thefilm surface temperature was elevated up to 40° C., then an alkalisolution having the composition shown below was applied onto one surfaceof the film at an application amount of 14 ml/m² using a bar coater, andtransported for 10 seconds under a steam-type far infrared heatermanufactured by NORITAKE Co., Ltd. while heating at 110° C.

Subsequently, 3 ml/m² of pure water was applied using the same barcoater.

Subsequently, water washing using a fountain coater and drainage usingan air knife were repeated three times, and then, the film wastransported to a drying zone for drying at 70° C. for 10 seconds tocreate a cellulose acylate film 2 which had been subjected to an alkalisaponification treatment.

Composition (parts by mass) of alkali solution Potassium hydroxide 4.7parts by mass Water 15.8 parts by mass Isopropanol 63.7 parts by massFluorine-containing surfactant SF-1 1.0 part by mass(C₁₄H₂₉O(CH₂CH_(2O))₂₀H) Propylene glycol 14.8 parts by mass

A coating liquid for forming an alignment film having the followingcomposition was continuously applied with a wire bar of 48, using thecellulose acylate film 2 which had been subjected to an alkalisaponification treatment. The resultant was dried with hot air at 60° C.for 60 seconds and further dried with hot air at 100° C. for 120 secondsto form an alignment film.

Composition of coating liquid for forming alignment film PVA(manufactured by Kuraray Ltd., product 2.4 parts by mass name “KURARAYPOVAL PVA-103” manufactured by Kuraray Co., Ltd.) Isopropyl alcohol 1.6parts by mass Methanol 36 parts by mass Water 60 parts by mass

The following coating liquid N was applied onto the cellulose acylatefilm 2 having the alignment film created above, aged at 60° C. for 60seconds, and then irradiated with ultraviolet rays at 1000 mJ/cm² in airusing an air-cooling metal halide lamp (manufactured by Eyegraphics Co.,Ltd.) at 70 mW/cm², and the alignment state was fixed to verticallyalign a rod-like polymerizable liquid crystal compound, thereby creatinga positive C plate film 1. The Rth at a wavelength of 550 nm was −60 nm.

Composition of coating liquid N for optically anisotropic layer Thefollowing liquid crystalline compound L-1 80 parts by mass The followingliquid crystalline compound L-2 20 parts by mass The following verticalaligning agent (S01) 1 part by mass for a liquid crystal compound (S01)Ethylene oxide-modified trimethylol propane 8 parts by mass triacrylate(V#360, manufactured by Osaka Organic Chemical Industry Ltd.) IRGACURE907 (manufactured by BASF) 3 parts by mass KAYACURE DETX (manufacturedby Nippon 1 part by mass Kayaku Co., Ltd.) The following compound B030.4 parts by mass Methyl ethyl ketone 170 parts by mass Cyclohexanone 30parts by mass

Creation of Circularly Polarizing Plate

The positive C plate film 2 created above was transferred to the side ofthe optically anisotropic layer of the λ/4 phase difference film 1through a pressure sensitive adhesive, and the cellulose acylate film 2was removed. In addition, the polarizing element of each of Examples 101to 115 and Comparative Examples 201 to 204 was adhered to the side ofthe cellulose acylate film 1 of the λ/4 phase difference film 1 througha pressure sensitive adhesive to obtain a circularly polarizing plate.

GALAXY S5 manufactured by SAMSUNG, having an organic EL panel (organicEL display element) installed therein, was disintegrated, the touchpanel to which the circularly polarizing plate was adhered was peeledfrom the organic EL display device, the circularly polarizing plate wasfurther peeled from the touch panel, and the organic EL display element,the touch panel, and the circularly polarizing plate were each isolated.Subsequently, the isolated touch panel was adhered again to the organicEL display element, which was further adhered to the touch panel suchthat the side of the circularly polarizing plate created above was thepanel side, thereby creating an organic EL display device.

With regard to the created organic EL display device, the sameevaluation as in the case using PURE-ACE WR (manufactured by TeijinLimited) as a ¼ wavelength plate was performed, and thus, it wasconfirmed that the same effect was exhibited in both of the case usingthe λ/4 phase difference film 1 as the ¼ wavelength plate and the caseof using the laminate of the positive C plate film 2 as the λ/4wavelength plate.

Creation of Alignment Film 21

The coating liquid 1 for a photo-alignment film was applied onto thealignment film 12 provided on a 40-μm TAC substrate (TG40, manufacturedby FUJIFILM Corporation), and dried at 90° C. for 1 minute. Thu obtainedapplied film was irradiated with linear polarized ultraviolet rays (anilluminance of 4.5 mW, an irradiation amount of 250 mJ/cm²) using apolarized ultraviolet exposure device to create an alignment film 21.Various refractive indices and film thicknesses of the obtainedalignment film 21 are shown in Table 2.

Creation of Alignment Films 22 to 27

Alignment films 22 to 27 were created by the same method as for thealignment film 21, except that the contents of the photo-alignmentmaterial E-1, DENACOL ACRYLATE DA-212 manufactured by Nagase ChemteXCorporation, and Poly(styrenesulfonic acid)sodium Salt E-2 manufacturedby Wako Pure Chemical Industries, Ltd., and the irradiation amounts ofthe linear polarized ultraviolet rays were changed as shown in Table 2.Various refractive indices and film thicknesses of each of the obtainedalignment films are shown in Table 2.

Creation of Alignment Film 28

The composition 10 for forming an alignment layer was applied onto thealignment film 12 provided on a 40-μm TAC substrate (TG40, manufacturedby FUJIFILM Corporation) by a spin coating method, and a support havingthe composition 10 for forming an alignment layer applied thereon wasdried in a hot plate at 80° C. for 5 minutes to remove the solvent,thereby forming a coating film.

The obtained coating film was irradiated with polarized ultraviolet rays(25 mJ/cm², ultra-high-pressure mercury lamp) to create an alignmentfilm 28.

Example 301 Creation of Anisotropic Light-Absorbing Film

The following liquid crystalline compound 2 was continuously appliedonto the obtained alignment film 21 with a wire bar of #5 to form anapplied film 301.

The applied film 301 was heated at 140° C. for 90 seconds and theapplied film 301 was cooled to room temperature.

Subsequently, the film was heated at 80° C. for 60 seconds and cooledagain to room temperature.

Thereafter, the film was irradiated with light for 60 seconds under anirradiation condition of an illuminance of 28 mW/cm², using ahigh-pressure mercury lamp, to create an anisotropic light-absorbingfilm (a thickness of 600 nm) on the alignment film 21.

Composition of liquid crystalline compound 2 Yellow azo coloring agentY-1 2.7 parts by mass Cyan azo coloring agent C-1 13.5 parts by massHigh-molecular liquid crystal compound P-1 101.1 parts by massPolymerization initiator IRGACURE819 1.0 part by mass (manufactured byBASF) Interface modifier F-1 0.5 parts by mass Cyclopentanone 617.0parts by mass Tetrahydrofuran 264.4 parts by mass

Creation of Oxygen Shielding Layer

The composition 2 for forming an oxygen shielding layer was continuouslyapplied onto the anisotropic light-absorbing film 301 with a wire bar of#5 and dried at 60° C. for 5 minutes to prepare a polarizing element inwhich the oxygen shielding layer was formed on the anisotropiclight-absorbing film. In this manner, a polarizing element of Example301 was created. The degree of alignment of the obtained polarizingelement is shown in Table 2.

Furthermore, the anisotropic light-absorbing film was peeled from thepolarizing element of Example 301, and the degree S of alignment wasmeasured by the above-mentioned method. The degree S of alignment of theanisotropic light-absorbing film is shown in Table 2.

Examples 302 to 310 and Comparative Examples 401 to 403

Anisotropic light-absorbing films were created on the alignment films 12and 21 to 28 by the same method as in Example 301, except that the blendratio of two kinds of dichroic substances was set to be the same as inExample 301 and only the solid fractions of the dichroic substances werechanged as in Table 2. In this manner, polarizing elements of Examples302 to 308 and Comparative Examples 401 to 404 were created.

In addition, the anisotropic light-absorbing film was peeled from thepolarizing element of each of Examples and Comparative Examples and thedegree S of alignment was measured by the above-mentioned method. Thedegree S of alignment of the anisotropic light-absorbing film is shownin Table 2.

Creation of Circularly Polarizing Plate

The above-mentioned positive C plate film 2 was transferred to the sideof the optically anisotropic layer of the λ/4 phase difference film 1through a pressure sensitive adhesive, and the cellulose acylate film 2was removed. In addition, the polarizing element of each of Examples 301to 308 and Comparative Examples 401 to 403 was adhered to the side ofthe cellulose acylate film 1 of the λ/4 phase difference film 1 througha pressure sensitive adhesive to obtain a circularly polarizing plate.

GALAXY S5 manufactured by SAMSUNG, having an organic EL panel (organicEL display element) installed therein, was disintegrated, the touchpanel to which the circularly polarizing plate was adhered was peeledfrom the organic EL display device, the circularly polarizing plate wasfurther peeled from the touch panel, and the organic EL display element,the touch panel, and the circularly polarizing plate were each isolated.Subsequently, the isolated touch panel was adhered again to the organicEL display element, which was further adhered to the touch panel suchthat the side of the circularly polarizing plate created above was thepanel side, thereby creating an organic EL display device.

Evaluation of Display Performance

With regard to each of the organic EL display devices obtained using thepolarizing elements of Examples 301 to 308 and Comparative Examples 401to 403, evaluation of the display performance was performed on the basisof the same evaluation of display performance and the same evaluationstandards as for the display device obtained, using the above-mentionedpolarizing element of Example 101. The evaluation results are shown inTable 2.

TABLE 2 Alignment film Material of Binder alignment film componentAverage Average Parts by UV Irradiation Parts by refractive refractiveSubstrate Type Type mass amount mJ/cm² Type mass index n_(ave) indexn₅₅₀ Example 301 TG40 Alignment film 21 E-1 1.0 250 — — 1.82 1.76Example 302 TG40 Alignment film 21 E-1 1.0 250 — — 1.82 1.76 Example 303TG40 Alignment film 22 E-1 1.0 700 — — 1.82 1.76 Example 304 TG40Alignment film 23 E-1 0.7 300 DA-212 0.3 1.76 1.71 Example 305 TG40Alignment film 24 E-1 0.7 300 E-2 0.3 1.82 1.77 Example 306 TG40Alignment film 25 E-1 0.3 300 DA-212 0.7 1.68 1.64 Example 307 TG40Alignment film 26 E-1 0.3 300 DA-212 0.7 1.68 1.64 Example 308 TG40Alignment film 27 E-1 0.3 300 DA-212 0.7 1.68 1.64 Comparative TG40Alignment film 12 Modified PVA — — — — 1.52 1.52 Example 401 ComparativeTG40 Alignment film 21 E-1 1.0 250 — — 1.82 1.76 Example 402 ComparativeTG40 Alignment film 28 C-2 — 25 — — 1.51 1.52 Example 403 Alignment filmAnisotropic light-absorbing film Refractive Film Amount of Solid Ratioindex thickness content of dichroic Degree S of Oxygen Display(n₄₅₀/n₅₅₀) anisotropy Δn (nm) substance alignment shielding layerperformance Example 301 1.09 0.22 15 14% 0.96 BA-1 C Example 302 1.090.22 15 9% 0.95 BA-1 C Example 303 1.09 0.35 18 13% 0.96 BA-1 C Example304 1.07 0.18 40 14% 0.96 BA-1 B Example 305 1.02 0.22 50 13% 0.96 BA-1B Example 306 1.05 0.15 110 15% 0.96 BA-1 B Example 307 1.05 0.15 60 14%0.96 BA-1 A Example 308 1.05 0.15 55 20% 0.97 BA-1 A Comparative 1.030.0 800 14% 0.95 BA-1 E Example 401 Comparative 1.09 0.22 15 7% 0.90BA-1 E Example 402 Comparative 1.01 0.05 100 13% 0.92 BA-1 E Example 403

In Table 2, it was confirmed that in a case where the degree ofalignment of the anisotropic light-absorbing film is 0.92 or more andthe average refractive index n_(ave) of the alignment film is in therange of 1.55 to 2.0, the display performance of the image displaydevice is excellent (Examples 301 to 308).

On the other hand, it was confirmed that in a case where the degree ofalignment of the anisotropic light-absorbing film is less than 0.92 andthe average refractive index n_(ave) of the alignment film is out of therange of 1.55 to 2.0, the display performance of the image displaydevice is deteriorated (Comparative Examples 401 to 403).

What is claimed is:
 1. A polarizing element comprising: an alignmentfilm; and an anisotropic light-absorbing film formed using a dichroicsubstance, wherein a degree S of alignment of the anisotropiclight-absorbing film is 0.92 or more, an average refractive indexn_(ave) at a wavelength of 400 to 700 nm of the alignment film is 1.55to 2.0, in a case where a refractive index of the anisotropiclight-absorbing film is defined as Nx₅₅₀ and a refractive index of thealignment film is defined as nx₅₅₀ in a direction in which an in-planerefractive index of the anisotropic light-absorbing film at a wavelengthof 550 nm is maximized, and a refractive index of the anisotropiclight-absorbing film is defined as Ny₅₅₀ and a refractive index of thealignment film is defined as ny₅₅₀ in a direction in-plane perpendicularto the direction in which the in-plane refractive index of theanisotropic light-absorbing film is maximized, Formula (1) is satisfied,|Nx ₅₅₀ −nx ₅₅₀ |+|Ny ₅₅₀ −ny ₅₅₀|<0.3  Formula (1).
 2. The polarizingelement according to claim 1, wherein an in-plane refractive indexanisotropy Δn at a wavelength of 550 nm of the alignment film is 0.10 ormore.
 3. The polarizing element according to claim 2, wherein therefractive index anisotropy Δn is 0.20 or more.
 4. The polarizingelement according to claim 1, wherein the average refractive indexn_(ave) is 1.55 to 1.80.
 5. The polarizing element according to claim 1,wherein an average refractive index n₅₅₀ at a wavelength of 550 nm ofthe alignment film is 1.55 to 1.75.
 6. The polarizing element accordingto claim 1, wherein a ratio of an average refractive index n₄₅₀ at awavelength of 450 nm of the alignment film to the average refractiveindex n₅₅₀ at a wavelength of 550 nm of the alignment film is 1.0 ormore.
 7. The polarizing element according to claim 1, wherein a contentof the dichroic substance is 8% to 22% by mass with respect to a totalsolid content mass of the anisotropic light-absorbing film.
 8. Thepolarizing element according to claim 1, wherein a thickness of thealignment film is 10 nm to 100 nm.
 9. The polarizing element accordingto claim 1, wherein the alignment film is a photo-alignment film formedusing a photoactive compound having a photoreactive group having an azogroup.
 10. The polarizing element according to claim 9, wherein thephotoactive compound is a compound represented by Formula (I),

in Formula (I), R²¹, R²², R²³, and R²⁴ each independently represent ahydrogen atom or a substituent, provided that at least one of R²¹, R²²,R²³, or R²⁴ represents a carboxy group, a sulfo group, or a saltthereof, and in Formula (I), m represents an integer of 1 to 4, nrepresents an integer of 1 to 4, o represents an integer of 1 to 5, prepresents an integer of 1 to 5, and in a case where m, n, o, and p areeach an integer of 2 or more, a plurality of R²¹'s, R²²'s, R²³'s, andR²⁴'s may be the same as or different from each other, respectively. 11.The polarizing element according to claim 9, wherein the photo-alignmentfilm includes a binder component having a refractive index of 1.50 to1.60, and a content of the binder component is 10% by mass or more withrespect to a total solid content mass of the photo-alignment film. 12.The polarizing element according to claim 1, wherein the alignment filmis a film formed using either or both of polyamic acid and polyimidecompounds.
 13. The polarizing element according to claim 1, wherein thedichroic substance includes a compound represented by Formula (II),

in Formula (II), R³¹, R³², R³³, R³⁴, and R³⁵ each independentlyrepresent a hydrogen atom or a substituent, R³⁶ and R³⁷ eachindependently represent a hydrogen atom or an alkyl group which may havea substituent, Q³¹ represents an aromatic hydrocarbon group, an aromaticheterocyclic group, or a cyclohexane ring group, which may have asubstituent, L³¹ represents a divalent linking group, A³¹ represents anoxygen atom or a sulfur atom, and R³⁶, R³⁷, and Q³¹ may have a radicallypolymerizable group as a substituent.
 14. The polarizing elementaccording to claim 1, wherein the anisotropic light-absorbing filmexhibits reverse wavelength dispersibility.
 15. The polarizing elementaccording to claim 1, further comprising a substrate, wherein thepolarizing element has the substrate, the alignment film, and theanisotropic light-absorbing film in this order.
 16. A circularlypolarizing plate comprising: the polarizing element according to claim1; and a ¼ wavelength plate.
 17. An image display device comprising: thepolarizing element according to claim 1; and an image display element.18. The polarizing element according to claim 2, wherein the averagerefractive index n_(ave) is 1.55 to 1.80.
 19. The polarizing elementaccording to claim 3, wherein the average refractive index n_(ave) is1.55 to 1.80.
 20. An image display device comprising: the circularlypolarizing plate according to claim 16; and an image display element.